Kramer, I also worked in the San Francisco Bechtel building. Right after my wife and I moved from Boston to San Francisco in 1990, my first job was for a Bechtel subcontractor, developing on Sun workstations. I worked for Bechtel until their Houston Omniport project went bankrupt.
I've still got a Z80 "microprofessor" trainer from about 1985. Its pretty cool - you can enter little Z80 assembly programs, run them, debug them, and access all the bus lines. I burned an EPROM with a loader program and plugged it into a trainer expansion socket so I could write assembly code on a PC, compile it to machine code then send it over RS232 to the trainer and the trainer would load, then run it.
I remember that those 8255s would reset all their outputs to zero whenever you changed any port direction. Grrr!
David B.
Whenever I go into a local eletronics shop here, they have packages of 8255 tutorials.
I had been thinking that there must be something terrific about these chips to be able to still be on the market.
But, you just pointing out an extremely important difference between them and what can be done now. Having all your ports temporarily go low would really fowl up a lot things.
I guess instant port direction changes [noparse][[/noparse]like the SPI and I2C] were just never considered an option.
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"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)
······································································ Warm regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan
I never knew about the issue because I always used the ports for a specific purpose and their direction never changed after initialization.· Does seem like (again its been awhile) I used to split a port for a 4 X 4 Keypad Scanner though.
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LOL... Gosh...
My Primary C64 was used for running a BBS... Angles Lair, located in Bayville, NJ.
3 1581's, 16 Megs of battery backed ram on a RAMLINK, system printer 2400 modem, Ran the software called DMBBS.
Cost me plenty, got the source code, a buddie and I became the "top ranked DMBBS modifiers"...
Got into a number of projects, including "networking" and "distrbuited processinge" with the C64, some drives, some creative wiring and programming.
I forgot the Rainbow color printer...
My CoCo2 had died sometime before, but the memory still lives on...
I still have my timex sinclair 1000, and a 16k memory pack...
I remember having "user meetings" -> turned out to be copying sessions
Once, we had an Amegia 500, IBM compatable and C64 compition in 4 areas...
I remember the Amegia won in only the 3D graphic, the IBM compatable in overall hardware... but the C64 kicked but.
Onwards, the Eliete's -> Well, my roots go deep there as well. I do recall the upstarts and the what nots...
(I seem to recall a rift or two... my "super" personality being what it was...)
Others have documented that time period...
/me wipes some tears... I do mis the C64 stuff, the BBS's and the want not... but, ya know, the PC today kicks..
Ok, just some bits from this old programmers bit bucket...
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Just tossing my two bits worth into the bit bucket
KK ·
Looks like you can do it all again on a Propeller. Just don't get too complicated too fast.
I had a CoCo which was my 'first' computer. I actually had a three potentiometer analog computer many years eariler, but I don't think that qualifies.
I started to build an S100 computer. First a back plane, then a CPU board, some big, big capacitors, then someone sold me an IMASI chassis complete for cheap, I got RAM, I got video, I even got a floppy disk card. But, I never got it all together. It was just to0 hard to input binary by switches, my first keyboard purchase was EBDIC, not ASCII. Had to fit it to a blank chassis. The floppy disk card wanted a BIOS ROM burned to get it running. I had CPM, but no BIOS.· There wasn't any web to get documentation and companies were going in and out of business weekly.
Why didn't I just follow the crowd with Apple IIEs?
Dumb and dumber.
It finally went to the Electronic Shop at George Washington H.S. in S.F. and I bought an ITT PC clone with an Epsom printer and very complete bundled software. It even included an Assembler which was documented cryptically like the IRS tax code.
I told the guy in the computer store that I would buy a complete computer that day if my credit was approved. I filled out my credit application as 'unemployed' and he couldn't believe it was accepted anyway. Cost about $2000USD.
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"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)
······································································ Warm regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan
I think the only thing I ever really liked about the Apple IIe were the games COMPUTE! would print in their magazine.· there was always a C64 and Apple IIe version, but the Apple versions were often more well written than their C64 counterparts.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔ Chris Savage Parallax Tech Support csavage@parallax.com
A favorite game of mine for the Apple IIe was "Jawbreaker" (I think that was what it was called - a Pacman clone). And who can forget "LodeRunner" from Broaderbund. Great games!
No I gave those magazines away back in the late 80's...By the early 90's I was well into Amiga Mode and my business had just taken off...Apples were something I repaired but stopped using.· There has got to be a website that has this material.· You should do a Google Search...
Lead Test Engineer said...
A favorite game of mine for the Apple IIe was "Jawbreaker" (I think that was what it was called - a Pacman clone). And who can forget "LodeRunner" from Broaderbund. Great games!
My two favorite Apple IIe games were Jordan VS Bird One on One (Loved breaking the backboard and watching the janitor come out and sweep up the broken glass)...And Conan, which was a weird but addictive little game...Oddly my favorite old original C=64 game was called, "Fort Apocalypse" and was a cool little helicopter side perspective game that came on a cassette tape!· But later it was Bionic Commando and Rambo (I forgot which one).· Let's not forget Tetris!
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔ Chris Savage Parallax Tech Support csavage@parallax.com
I've played it on just about every platform I've used, except the ND5700 mainframe we had at the office...
I've even used it on a VT100 terminal connected to a Digital VAX.
Snake wasn't a bad game, either...
The most challenging version I've tried is on the Psion Organiser II series PDAs.
They have 2 or 4-line LCDs, but the programmer used custom-defined character-graphics to split it into 4 or 8 lines...
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Does anybody read Martin Gardner?
He was a monthly contributor to Scientific American in reguards to games, mathmatical puzzles, magic, and debunking hoaxes.
I have a couple of his books and I am waiting for a few more to come from the U.S.
You can easily come up with some new games -- like Sudoku, that math puzzle that is next to all the crosswords in the newspaper these days.
Tetris is still alive and well in Taiwan. Of course we have music from the 1950s and 1960s too. Sometimes it feels like a time warp. Asteroids with all the different dimension shifts really got my attenton: negative gravity, bounce at the borders or wrap around, get sucked into a sun, navigating curved space. You could always add a few passing comets, a meteor shower, and a vanishing worm hole. [noparse][[/noparse]Very simple graphics that feel a very complex fantasy world.]
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"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)
······································································ Warm regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan
I prefer the 'Evil' level of Sudoku over at http://www.websudoku.com for my lunchtime entertainment. (No, I don't always manage to sole it during my lunchbreak... )
As for 50s and 60s music...
Guess what most of the 3000 songs on my iPod is...
Although I'm probably younger than most of you (I'm 23), I feel more of a connection to the old school programmers than the other CS students my age. I guess I'm something of an anachronism, though I keep my skills up in both the very old computing stuff, and the newest stuff these days.
You see, even though the rest of the world was using Windows 95 at the time, I learned to program on a Z-80 machine running CP/M. Green monochrome screen and everything.
When I was growing up, my family was too poor to buy a computer, and we lived in an area where most people were poor. So there were some very old computers floating around because people couldn't afford to upgrade every year. When I was 12 someone gave me a wonderful old computer called the Epson QX-10. Gosh I wish I still had that. Anyhow it came as sort of a "some assembly required". Luckily, even though I'd never dreamed of owning a computer, I'd been a wizard with electronics since before kindergarten, so I was able to fix the hardware. (Really, since before kindergarten: My parents tell me that when I was 3, I took two broken toy helicopters completely apart, and built up a working toy helicopter out of the pieces. They weren't even the same brands. You can guess I was a bit autistic-ish when I was a kid. Kept to myself, took everything apart, never spoke to anyone my own age for the first 7 years of school, etc. Never diagnosed because I could carry on a bright conversation with an adult on que, but they didn't know that I spent the rest of my life in my own private world where there weren't any people, just electronics to take apart and machines to examine. People think I've grown out of it, but, mwhaa ha ha, the truth is I've merely perfected a human emulation program that I run in my head when I need to pass as a normal person. I do care about other people, very much, I just have an "alien" perspective.)
Anyhow the QX-10 actually came with an assembler but I didn't have any documentation on that. During the whole time I had that computer, the power of assembly was right there and I never realized I had an assembler for it.
My very first programming was in, of all things, dBASE II for CP/M. It was a pidgin BASIC with like, 3 SQL keywords thrown in for good measure. You had 80 integer variables and you could store things in tables on disk. But it had loops and block if/endif and no line numbers. I got started with it because the computer had come with a slim book on dBASE that was written by a good author, very witty and down-to-Earth. I don't really remember encountering any sort of learning curve when it came to picking up these "CS 1 course"- level concepts. I just... grokked them. It was like finding religion, I didn't learn basic programming skills so much as experience a revelation - aha! of course! So THAT'S how it is! And so forth.
Of course I immediately tried to write games. The attempts never went well - dBASE II was remarkably similar to pBASIC for the BASIC stamp 2 in language constructs, speed, and variable space, and I love the BASIC Stamp 2 and all, but it would not be easy to code, say, Mario Bros. on a BASIC Stamp. I even tried to write an RPG game in the spreadsheet program that came with the office software package, because you could redefine the screen font to include little trees and swords and whatnot. Once I learned dBASE II, it was pretty apparent to me that a spreadsheet is nothing but a 2-dimensional programming language with wacky rules. Turned out the macros for the spreadsheet lacked the power to do an interactive game, but I bet you could do it with Excel! - I've seen people do really crazy stuff with Excel.
Later I found Microsoft BASIC-A on a disk with the programmer's guide and I remember reading a whole chapter on strings, going, "What the hell is a 'string'?" because the programmer's guide for dBASE II only talked about integer variables and the Microsoft people had assumed you already knew what a string was. At Microsoft some noble soul was trying to get a paragraph explaining strings put in "for that 12 year old kid who sleeps in a closet, who, with no other human contact, has picked up this programmer's guide and is trying to learn computer science from it." But that guy got overruled.
I really did sleep/live in a closet. It was quaint, actually. I had a "mini"-twin mattress on the floor, and my QX-10 on half a coffee table at the foot of my bed. I'd boot up my computer and do a little hacking every morning before I brushed my teeth, and when I slept the green glow from the monochrome screen was like a nightlight. I had about 100 books on a shelf running lengthwise near the ceiling, and every so often a paperback would fall off the pile and land on my head while I was asleep. That'll make a guy get up with a jump! I had tools for working with wood and with electronics, and any time I needed or wanted a piece of "closet sized" furniture or some amenity, I'd fabricate it myself. (Hence the half of a coffee table; I chopped a garage sale coffee table in half so it would fit shortways and then reattached the legs.)
I'm still holding out on this newfangled "strings" concept. We got along fine with just integers in dBASE II.
I had some fun and some frustrations working with the hardware too. I remember having to pull styrofoam out of the disk drives to get them to work. It was lodged behind the voice coils and keeping the head from reaching all the tracks. Now how did styrofoam chunks get through the thin floppy slots? The machine also used the same chips for system RAM as it did for video RAM, lots and lots of DIP chips. When the system RAM started going bad, I would swap the offending chip with one from video RAM, because it won't crash the system if a pixel goes out on video RAM, so I wanted all my flaky chips on the video board and all my good chips on the system board.
Eventually the system reached a point where it would no longer respond to anything I did to fix it, and my father forced me to get rid of it. He was very antagonistic to me spending time on a computer and would daily threaten to throw it out when it was running; with it not even running at all, there wasn't much argument I could give. I wish I still had it. I didn't know then what I know now, but it really was a very simple machine and with the skills I have now I could have fixed anything wrong with it indefinitely. At least I took all the socketed chips out before I let it go. I still have the processor, and I suppose I can feel some sense of continuance because an 8255 chip I saved from it has now become part of the Propeller/68K computer I'm building. Ah, if I did still have it, what would I do with it? It'd just sit there. But I would have liked to make an emulator for the QX-10.
After the QX-10 died, my uncle built for me and shipped to me a 486 machine, where I spent a lot of time on QBASIC. Every time I had trignometry homework, I would write a custom QBASIC program to calculate the answers for me and show me the work to write down. Of course that took ten times longer than it would to actually do the homework, but if you point that out, you're not thinking like a programmer.
They also had QBASIC and Nibbles on the school's computers, and whenever I had the chance I would hack the game code to make it do interesting things. I learned a lot this way, and having my friends looking over my shoulder while I coded shaped the way I learned to code, so that now I write as though I have a friend looking over my shoulder and I'm explaining to him what I'm doing as I go along.
I need to make a QBASIC emulator for the Propeller, so we can all play Gorillas, and Nibbles, on our televisions.
I also picked up a Compaq Portable around this time, one of those giant luggable computers with the keyboard base covering a built-in green monitor and disk drive. That too I no longer have.
But I do still have 2 Tandy 1000's, an RL that I added a hard drive to, and an RLX that comes with one. Nice little machines. My siblings and I used to play Lemmings and Hangman on them. We were hangman maniacs. One time I correctly guessed "bilateral" from just the vowels: "_ i _ a _ e _ a _"
··· There are still a few of us that use QuickBASIC (commercial version of QBASIC)...Myself for one and Beau Schwabe.· It's great for testing BASIC code/concepts in a PC environment.· And BTW, don't know how much you read of this thread, but the Z80 will always be very near/dear to my heart and the CPU I knew best back in the day.· Take care.
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Z80 assembly was the first assembly language I learned on my Timex Sinclear 1000 (ZX81 clone).
The TS1000 was terribly slow in BASIC. But in assembly...Hold on to your hats...
I remember thinking "The computer understands BASIC, how does it translate assembly into BASIC ?".
At the time I had no idea what assembly was, but I soon learned.
It was like a drug, I would write assembly in study hall. I knew most of the hex code for the op-code by heart.
Oh fun days those were...
I did have one good friend who had a CoCo computer and was learning assembly too. I would spend the night at his house, and we would not sleep. We would stay up ALL night writing programs (games mostly).
Then I got a TS2068 and wrote a complete "space invaders" type game in assembly. It took about a year.
My parents worried about me too. I spent unless hours in my room on the computer.
I recently got the book "Understanding the Apple II". It details the hardware of the Apple II and it really shows how much of a genius Woz really was. Talk about thinking "outside of the box", hell he didn't even know what "the box" was.
Bean.
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Cheap used 4-digit LED display with driver IC·www.hc4led.com
Bean (Hitt Consulting) said...(trimmed) I did have one good friend who had a CoCo computer and was learning assembly too. I would spend the night at his house, and we would not sleep. We would stay up ALL night writing programs (games mostly).
Bean,
· CoCo?· Wow...Memories...I think it was the CoCo II I used to gain a grasp on 6809 assembly.· Wasn't much use for anything else since I couldn't handle the "non-standard" screen format (non-standard in comparison to the VIC-20 & C=64 I had been using the most).·
·· I know what you mean about memorizing Op-Codes...While I didn't memorize them all, there were a few groups I did because of the way they were handled differently depending on just a few bits being different.· Just out of curiosity, did you ever mess with the Z8?· Never bothered myself...It was in 1997 when I decided to give up Z80-based designed and move to a microcontroller...I thought about the Z8, but by 2000 I had already gotten into the BS2.· Kicker is, I had built almost all of my Z80 controllers with the same memory configuration and the Z8 was different, so I decided if I have to start over anyway...
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Nope,
I never messed with the Z8. I remember looking at it and it looked interesting.
I learned Z80 assembly, then a little 6502 (on the apple), then 8086 (amstrad PC clone), then PIC, then SX.
Who remembers calculating relative jump offset by hand ? Oh what fun. Change one instruction, and calculate all the jumps again.
Bean.
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Cheap used 4-digit LED display with driver IC·www.hc4led.com
I had an Apple II and even built some expansion boards for it. The bus was very easy to use. In the 70's, I worked for Datapoint which was a business computer company. They had contracted with Texas Instruments and Intel to develop a single chip version of their CPU. Neither company successfully delivered, but their designs became the Intel 8008 which later became the 8080, then 8086. A lot of the quirks of the PC instruction set are directly due to the quirks of the Datapoint instruction set.
I used to print out my own HEX line numbered paper and write my assembly out by hand...· The HEX line numbers made it "easier" to calculate relative jumps.
My first assembly was disguised as an 8K ATARI game cartridge... The 30-key keyboard consisted of interlocking both of the 3x5 game controllers together and
using inlays over the controller pad. The flavor of assembly for the ATARI was based around the 6502 processor.
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IC Layout Engineer
Parallax, Inc.
Doing assembly for the Z80 on paper is fun, I'll admit, but doing disassembly by hand is much more fun...
It's a hobby of mine...
There's been a few times that I've seen something strange happening, like a register being cleared, then loaded with a value from RAM, a loop written to copy a block of data to another location, things like that...
And I've come to the conclusion that many people who wrote code for the Z80 either didn't KNOW the chip, or they used either a cross-assembler for the 8080, or a poorly optimized high-level language compiler to do the work.
What's worse is that I'm not talking about games or utilities here, but about the ROM-chips and built-in programs in some computers.
You can tell that an 8080/8085 programmer has done the work if they never use the EXX instructions when handling interrupts, and doing unnecessary instructions(like clearing a register, then loading it) is a sure sign of a high-level language being used.
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Don't visit my new website...
I'm in the process of reliving some of my TS1000 / ZX81 days again. I am trying to buy a few of them and interface and ML books to do some interfacing projects with BS2 or SX-28 chips. However, the first and only 2 TS1000's bought on Ebay came to me not working. Both had bad ULA chips (video giving strange displays) and one had a keyboard connection that simply cracked into pieces too. I'm trying to order a couple more but are more cautious to ask the seller if he has tested them and if he knows they are working. The first one I had, the user said that he had no problems but people lie to get rid of stuff too. Lesson Learned.
I personally belive that the problem isn't with the age of the person or·who you know, but rather that much less is required to work on computers.
My dad brought home an Apple II plus with extended memory of 64K and we were in awe of its power. User friendly computer languages and point-n-click shortcuts are become so run of the mill that to consider actually KNOWING your stuff is virtually unheard of.
Example - I am learning LISP, my brother in law likes to work on the computer and can do a considerable amount, but when it comes to him understanding why things happen or how to use error handeling he goes nuts. Add to that he knows, at best, part of VBA and he is considered a "computer geek". Truth is if you learned things about programming back when there wasn't a debugger or learned with a language that tells you theres a probelm but doesn't identifiy what, your grasp of computers is significantly better. In my opinion.
In some ways I miss the days of having to label every line of code and needing to think, on the other hand it was very frustrating at times. Basically you don't really have to think with a lot of the most user friendly languages and those who actually program where you have to think are told it must be really hard.
Oh man, I just got sucked in. Spent the last half hour or so, reading through this thread. It really should be it's own forum topic catagory.
I'm here because modern computing isn't really that much fun anymore. It pays the bills, but that's about it. --time to start the computing hobby aspect of things again.
I got started on a TRS80 Model I. Wrote elementary BASIC programs to calculate things, like propagation windows for radio. My mentor was a HAM radio operator, who introduced me to electronics and computers at the same time. The model I was a neighbors machine, and it didn't take long until I had to have my own. I eventually got an Atari 400 and tricked it out with real keyboard and 48K of RAM. A good friend ended up with a CoCo 2, also expanded to 64K. We both had cassette drives for the longest time. On that note, the CoCo cassette driver software was the best. It was extremely tolerant of speed changes and supported filenames, and was quite fast. The atari cassette was much worse, but fairly reliable as long as one used the older thicker tapes. (C15's and C30's were the very best at normal bias formulation)
Wrote a bunch of stuff in BASIC, largely games, but a few HAM radio oriented things too. Speed became an issue real quick, also games brought with them some pressure to more fully understand the machine. I wanted to be able to make my computer do those things!
So the assembly language journey began. First 6502, then 6809. The latter was quite likely the most powerful and elegant 8 bitter ever made. (Apologies to you Z80 folks here!) I flunked out of a drafting class in High School because I was flowcharting and diagramming data structures for assembly language programs instead of drawing chain links! Funny, that today a significant part of my professional job involves training people in the finer points of MCAD! Anyway, having the large paper space was just great for sorting out all the little details. Binary graphic objects, storage, program flow, memory map, etc... One C sized sheet of paper could hold, the graphical representations, plus code snippets, and some logic.
Frankly, I loved that time more than any other. It was possible to completely understand the inner workings of the machine. Somebody here mentioned COMPUTE! magazine. I'd like to add Creative Computing and BYTE! to the list as well. It was possible to learn the core elements of computing from rags available in your local grocery store! For a small town kid like I was, this changed my life. If one followed the lessons presented in those publications, in the form of demos games and other type in applications, one earned a fair knowledge of computing.
I'm sure everyone here understands the feeling of getting your first assembly project right. My first one was done totally by hand, on paper. Looking up the OPcodes in the 6502 data book, calculating branch offsets, figuring out where data should live and where it can live. It's amazing that any of us actually got our start at all. Who would spend a week laying out a program that could easily crash and burn in less time than it takes to blink an eye?
I found learning binary numbers very interesting and educational. The most difficult part of low level programming is learning that computers really only do two things: add numbers together and move them around. A real world representation is exactly what you think it is! Putting hello world onto your television really comes down to understanding the machine in use, then making your choice as to how best represent hello world in a manner that when evoked, others will understand!
As I progressed through my career, I ended up doing a lot of hands on manufacturing. (Prototype mechanic in precision sheet metal) Loved the work and NC programming was lots of fun --similar to working with the 8bitters actually. Started with that, the same way I did early computers. Mapped out what needed to happen, then wrote code for each piece. IMHO, this is a skill somewhat lost today. I think it still has value.
When I once again entered into computing for professional reasons, it was on SGI IRIX machines. Nice, beautiful UNIX boxes that had lots of high-end functionality and an elegance that really attracted me. Still use an O2 to this day, as a matter of fact. That time has now gone, leaving us mostly with bland PC's that largely run win32 OSes. No fun at all. --Enter Linux and OSS in general.
One thing that struck me as being obvious in the early times was the open nature of things. If you wanted to learn about something, you looked at it. Disessembling games to understand how they did things was easy. --Often you could just read it right off the disk and go from there. Make some changes, boot the thing and see what happened. Of course that did involved defeating copy protection, but was well worth it, IMHO. Linux / OSS is that way today and it's just about the only thing that makes modern machines fun. Professionally, I've a win XP laptop that I use to teach MCAD and support engineering data management systems on, but somebody else paid for it. My own personal machines are the Atari 400 (yes it still works!), coupla SGI machines from e-bay, and a PC running Ubuntu. I'm not missing anything.
Somewhere in the last few years, the nostalga bug ended up biting. Found myself programming classic 8bit machines again, via emulation. Somebody wrote a compiled basic for the atari 2600 and I've toyed with that plenty. (Wonderful old hardware in that the display system is completely software driven. The smarter you are, the better the display is. New techniques are still being discovered 30 years later!)
I'm here, getting ready to order a prop demo board, from an off hand comment made on one of the classic computing forums. Took one look at the prop and realized it's gonna be just as much fun as the old 8bitters was. Way back when, I used the Atari I/O ports to control things. (fried a coupla of them too.) There was little overhead in that environment and that's where the appeal is. One can blend hardware and software together to do something, without a lot of expense or hassle.
Having caught up with the forums here, with this thread in particular, I realize I've been missing out. No time like the present to get started again! The open nature of this community, that surrounds the parallax product offerings, is just great. (Hope you guys can keep it up, because I think it's gonna suck in a few younger people, who would not otherwise get the same experience through more mainstream means.)
Thanks for the memories, I'm sure this thread will continue to grow. It's just too good of a time to not.
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Chris Savage
Parallax Tech Support
csavage@parallax.com
I've still got a Z80 "microprofessor" trainer from about 1985. Its pretty cool - you can enter little Z80 assembly programs, run them, debug them, and access all the bus lines. I burned an EPROM with a loader program and plugged it into a trainer expansion socket so I could write assembly code on a PC, compile it to machine code then send it over RS232 to the trainer and the trainer would load, then run it.
I remember that those 8255s would reset all their outputs to zero whenever you changed any port direction. Grrr!
Whenever I go into a local eletronics shop here, they have packages of 8255 tutorials.
I had been thinking that there must be something terrific about these chips to be able to still be on the market.
But, you just pointing out an extremely important difference between them and what can be done now. Having all your ports temporarily go low would really fowl up a lot things.
I guess instant port direction changes [noparse][[/noparse]like the SPI and I2C] were just never considered an option.
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"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)
······································································ Warm regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan
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Chris Savage
Parallax Tech Support
csavage@parallax.com
My Primary C64 was used for running a BBS... Angles Lair, located in Bayville, NJ.
3 1581's, 16 Megs of battery backed ram on a RAMLINK, system printer 2400 modem, Ran the software called DMBBS.
Cost me plenty, got the source code, a buddie and I became the "top ranked DMBBS modifiers"...
Got into a number of projects, including "networking" and "distrbuited processinge" with the C64, some drives, some creative wiring and programming.
I forgot the Rainbow color printer...
My CoCo2 had died sometime before, but the memory still lives on...
I still have my timex sinclair 1000, and a 16k memory pack...
I remember having "user meetings" -> turned out to be copying sessions
Once, we had an Amegia 500, IBM compatable and C64 compition in 4 areas...
I remember the Amegia won in only the 3D graphic, the IBM compatable in overall hardware... but the C64 kicked but.
Onwards, the Eliete's -> Well, my roots go deep there as well. I do recall the upstarts and the what nots...
(I seem to recall a rift or two... my "super" personality being what it was...)
Others have documented that time period...
/me wipes some tears... I do mis the C64 stuff, the BBS's and the want not... but, ya know, the PC today kicks..
Ok, just some bits from this old programmers bit bucket...
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Just tossing my two bits worth into the bit bucket
KK
·
If anyone want to read more about the venerable 6502 processor, check out http://www.6502.org
A good site for similar info on the Z80 would be http://www.z80.info or here if you want to see it created on GLASS!
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Don't visit my new website...
I had a CoCo which was my 'first' computer. I actually had a three potentiometer analog computer many years eariler, but I don't think that qualifies.
I started to build an S100 computer. First a back plane, then a CPU board, some big, big capacitors, then someone sold me an IMASI chassis complete for cheap, I got RAM, I got video, I even got a floppy disk card. But, I never got it all together. It was just to0 hard to input binary by switches, my first keyboard purchase was EBDIC, not ASCII. Had to fit it to a blank chassis. The floppy disk card wanted a BIOS ROM burned to get it running. I had CPM, but no BIOS.· There wasn't any web to get documentation and companies were going in and out of business weekly.
Why didn't I just follow the crowd with Apple IIEs?
Dumb and dumber.
It finally went to the Electronic Shop at George Washington H.S. in S.F. and I bought an ITT PC clone with an Epsom printer and very complete bundled software. It even included an Assembler which was documented cryptically like the IRS tax code.
I told the guy in the computer store that I would buy a complete computer that day if my credit was approved. I filled out my credit application as 'unemployed' and he couldn't believe it was accepted anyway. Cost about $2000USD.
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"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)
······································································ Warm regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan
Post Edited (Kramer) : 3/1/2006 2:52:15 PM GMT
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Chris Savage
Parallax Tech Support
csavage@parallax.com
I just happen to have a IIe that I received recently, and well... need to test that it works...
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Don't visit my new website...
http://en.wikipedia.org/wiki/COMPUTE!
This site claims to have the full text of 44 issues...
http://www.atarimagazines.com/compute/
Now, isn't Google a really good friend??· That was just the first few matches...
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Chris Savage
Parallax Tech Support
csavage@parallax.com
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Chris Savage
Parallax Tech Support
csavage@parallax.com
I've played it on just about every platform I've used, except the ND5700 mainframe we had at the office...
I've even used it on a VT100 terminal connected to a Digital VAX.
Snake wasn't a bad game, either...
The most challenging version I've tried is on the Psion Organiser II series PDAs.
They have 2 or 4-line LCDs, but the programmer used custom-defined character-graphics to split it into 4 or 8 lines...
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Don't visit my new website...
He was a monthly contributor to Scientific American in reguards to games, mathmatical puzzles, magic, and debunking hoaxes.
I have a couple of his books and I am waiting for a few more to come from the U.S.
You can easily come up with some new games -- like Sudoku, that math puzzle that is next to all the crosswords in the newspaper these days.
Tetris is still alive and well in Taiwan. Of course we have music from the 1950s and 1960s too. Sometimes it feels like a time warp. Asteroids with all the different dimension shifts really got my attenton: negative gravity, bounce at the borders or wrap around, get sucked into a sun, navigating curved space. You could always add a few passing comets, a meteor shower, and a vanishing worm hole. [noparse][[/noparse]Very simple graphics that feel a very complex fantasy world.]
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"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)
······································································ Warm regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan
As for 50s and 60s music...
Guess what most of the 3000 songs on my iPod is...
Well... what isn't 'oldfashioned' radio-theatre, like http://www.doctorfloyd.com
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Don't visit my new website...
You see, even though the rest of the world was using Windows 95 at the time, I learned to program on a Z-80 machine running CP/M. Green monochrome screen and everything.
When I was growing up, my family was too poor to buy a computer, and we lived in an area where most people were poor. So there were some very old computers floating around because people couldn't afford to upgrade every year. When I was 12 someone gave me a wonderful old computer called the Epson QX-10. Gosh I wish I still had that. Anyhow it came as sort of a "some assembly required". Luckily, even though I'd never dreamed of owning a computer, I'd been a wizard with electronics since before kindergarten, so I was able to fix the hardware. (Really, since before kindergarten: My parents tell me that when I was 3, I took two broken toy helicopters completely apart, and built up a working toy helicopter out of the pieces. They weren't even the same brands. You can guess I was a bit autistic-ish when I was a kid. Kept to myself, took everything apart, never spoke to anyone my own age for the first 7 years of school, etc. Never diagnosed because I could carry on a bright conversation with an adult on que, but they didn't know that I spent the rest of my life in my own private world where there weren't any people, just electronics to take apart and machines to examine. People think I've grown out of it, but, mwhaa ha ha, the truth is I've merely perfected a human emulation program that I run in my head when I need to pass as a normal person. I do care about other people, very much, I just have an "alien" perspective.)
Anyhow the QX-10 actually came with an assembler but I didn't have any documentation on that. During the whole time I had that computer, the power of assembly was right there and I never realized I had an assembler for it.
My very first programming was in, of all things, dBASE II for CP/M. It was a pidgin BASIC with like, 3 SQL keywords thrown in for good measure. You had 80 integer variables and you could store things in tables on disk. But it had loops and block if/endif and no line numbers. I got started with it because the computer had come with a slim book on dBASE that was written by a good author, very witty and down-to-Earth. I don't really remember encountering any sort of learning curve when it came to picking up these "CS 1 course"- level concepts. I just... grokked them. It was like finding religion, I didn't learn basic programming skills so much as experience a revelation - aha! of course! So THAT'S how it is! And so forth.
Of course I immediately tried to write games. The attempts never went well - dBASE II was remarkably similar to pBASIC for the BASIC stamp 2 in language constructs, speed, and variable space, and I love the BASIC Stamp 2 and all, but it would not be easy to code, say, Mario Bros. on a BASIC Stamp. I even tried to write an RPG game in the spreadsheet program that came with the office software package, because you could redefine the screen font to include little trees and swords and whatnot. Once I learned dBASE II, it was pretty apparent to me that a spreadsheet is nothing but a 2-dimensional programming language with wacky rules. Turned out the macros for the spreadsheet lacked the power to do an interactive game, but I bet you could do it with Excel! - I've seen people do really crazy stuff with Excel.
Later I found Microsoft BASIC-A on a disk with the programmer's guide and I remember reading a whole chapter on strings, going, "What the hell is a 'string'?" because the programmer's guide for dBASE II only talked about integer variables and the Microsoft people had assumed you already knew what a string was. At Microsoft some noble soul was trying to get a paragraph explaining strings put in "for that 12 year old kid who sleeps in a closet, who, with no other human contact, has picked up this programmer's guide and is trying to learn computer science from it." But that guy got overruled.
I really did sleep/live in a closet. It was quaint, actually. I had a "mini"-twin mattress on the floor, and my QX-10 on half a coffee table at the foot of my bed. I'd boot up my computer and do a little hacking every morning before I brushed my teeth, and when I slept the green glow from the monochrome screen was like a nightlight. I had about 100 books on a shelf running lengthwise near the ceiling, and every so often a paperback would fall off the pile and land on my head while I was asleep. That'll make a guy get up with a jump! I had tools for working with wood and with electronics, and any time I needed or wanted a piece of "closet sized" furniture or some amenity, I'd fabricate it myself. (Hence the half of a coffee table; I chopped a garage sale coffee table in half so it would fit shortways and then reattached the legs.)
I had some fun and some frustrations working with the hardware too. I remember having to pull styrofoam out of the disk drives to get them to work. It was lodged behind the voice coils and keeping the head from reaching all the tracks. Now how did styrofoam chunks get through the thin floppy slots? The machine also used the same chips for system RAM as it did for video RAM, lots and lots of DIP chips. When the system RAM started going bad, I would swap the offending chip with one from video RAM, because it won't crash the system if a pixel goes out on video RAM, so I wanted all my flaky chips on the video board and all my good chips on the system board.
Eventually the system reached a point where it would no longer respond to anything I did to fix it, and my father forced me to get rid of it. He was very antagonistic to me spending time on a computer and would daily threaten to throw it out when it was running; with it not even running at all, there wasn't much argument I could give. I wish I still had it. I didn't know then what I know now, but it really was a very simple machine and with the skills I have now I could have fixed anything wrong with it indefinitely. At least I took all the socketed chips out before I let it go. I still have the processor, and I suppose I can feel some sense of continuance because an 8255 chip I saved from it has now become part of the Propeller/68K computer I'm building. Ah, if I did still have it, what would I do with it? It'd just sit there. But I would have liked to make an emulator for the QX-10.
After the QX-10 died, my uncle built for me and shipped to me a 486 machine, where I spent a lot of time on QBASIC. Every time I had trignometry homework, I would write a custom QBASIC program to calculate the answers for me and show me the work to write down. Of course that took ten times longer than it would to actually do the homework, but if you point that out, you're not thinking like a programmer.
They also had QBASIC and Nibbles on the school's computers, and whenever I had the chance I would hack the game code to make it do interesting things. I learned a lot this way, and having my friends looking over my shoulder while I coded shaped the way I learned to code, so that now I write as though I have a friend looking over my shoulder and I'm explaining to him what I'm doing as I go along.
I need to make a QBASIC emulator for the Propeller, so we can all play Gorillas, and Nibbles, on our televisions.
I also picked up a Compaq Portable around this time, one of those giant luggable computers with the keyboard base covering a built-in green monitor and disk drive. That too I no longer have.
But I do still have 2 Tandy 1000's, an RL that I added a hard drive to, and an RLX that comes with one. Nice little machines. My siblings and I used to play Lemmings and Hangman on them. We were hangman maniacs. One time I correctly guessed "bilateral" from just the vowels: "_ i _ a _ e _ a _"
Anyone wondering about the QX-10?
I don't own one of those, but I have the HX-20(The world's first laptop), it's successor the PX-4 and the PX-8.
nice HW all around.
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Don't visit my new website...
··· There are still a few of us that use QuickBASIC (commercial version of QBASIC)...Myself for one and Beau Schwabe.· It's great for testing BASIC code/concepts in a PC environment.· And BTW, don't know how much you read of this thread, but the Z80 will always be very near/dear to my heart and the CPU I knew best back in the day.· Take care.
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Chris Savage
Parallax Tech Support
Z80 assembly was the first assembly language I learned on my Timex Sinclear 1000 (ZX81 clone).
The TS1000 was terribly slow in BASIC. But in assembly...Hold on to your hats...
I remember thinking "The computer understands BASIC, how does it translate assembly into BASIC ?".
At the time I had no idea what assembly was, but I soon learned.
It was like a drug, I would write assembly in study hall. I knew most of the hex code for the op-code by heart.
Oh fun days those were...
I did have one good friend who had a CoCo computer and was learning assembly too. I would spend the night at his house, and we would not sleep. We would stay up ALL night writing programs (games mostly).
Then I got a TS2068 and wrote a complete "space invaders" type game in assembly. It took about a year.
My parents worried about me too. I spent unless hours in my room on the computer.
I recently got the book "Understanding the Apple II". It details the hardware of the Apple II and it really shows how much of a genius Woz really was. Talk about thinking "outside of the box", hell he didn't even know what "the box" was.
Bean.
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Cheap used 4-digit LED display with driver IC·www.hc4led.com
Low power SD Data Logger www.sddatalogger.com
SX-Video Display Modules www.sxvm.com
There are only two guaranteed ways to become weathy.
Spend less than you make.
Make more than you spend.
·
· CoCo?· Wow...Memories...I think it was the CoCo II I used to gain a grasp on 6809 assembly.· Wasn't much use for anything else since I couldn't handle the "non-standard" screen format (non-standard in comparison to the VIC-20 & C=64 I had been using the most).·
·· I know what you mean about memorizing Op-Codes...While I didn't memorize them all, there were a few groups I did because of the way they were handled differently depending on just a few bits being different.· Just out of curiosity, did you ever mess with the Z8?· Never bothered myself...It was in 1997 when I decided to give up Z80-based designed and move to a microcontroller...I thought about the Z8, but by 2000 I had already gotten into the BS2.· Kicker is, I had built almost all of my Z80 controllers with the same memory configuration and the Z8 was different, so I decided if I have to start over anyway...
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Chris Savage
Parallax Tech Support
I never messed with the Z8. I remember looking at it and it looked interesting.
I learned Z80 assembly, then a little 6502 (on the apple), then 8086 (amstrad PC clone), then PIC, then SX.
Who remembers calculating relative jump offset by hand ? Oh what fun. Change one instruction, and calculate all the jumps again.
Bean.
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Cheap used 4-digit LED display with driver IC·www.hc4led.com
Low power SD Data Logger www.sddatalogger.com
SX-Video Display Modules www.sxvm.com
There are only two guaranteed ways to become weathy.
Spend less than you make.
Make more than you spend.
·
I used to print out my own HEX line numbered paper and write my assembly out by hand...· The HEX line numbers made it "easier" to calculate relative jumps.
My first assembly was disguised as an 8K ATARI game cartridge... The 30-key keyboard consisted of interlocking both of the 3x5 game controllers together and
using inlays over the controller pad.
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Beau Schwabe
IC Layout Engineer
Parallax, Inc.
My first dog (when I was a kid) was named Byte. It used to make me made when people spelled it "bite".
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Coders' Hangout
A place for programmers to hangout!
http://www.codershangout.com
METROID?
Metroid Classic
It's a hobby of mine...
There's been a few times that I've seen something strange happening, like a register being cleared, then loaded with a value from RAM, a loop written to copy a block of data to another location, things like that...
And I've come to the conclusion that many people who wrote code for the Z80 either didn't KNOW the chip, or they used either a cross-assembler for the 8080, or a poorly optimized high-level language compiler to do the work.
What's worse is that I'm not talking about games or utilities here, but about the ROM-chips and built-in programs in some computers.
You can tell that an 8080/8085 programmer has done the work if they never use the EXX instructions when handling interrupts, and doing unnecessary instructions(like clearing a register, then loading it) is a sure sign of a high-level language being used.
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Don't visit my new website...
Anyway, someone posted news asbout a RS323/BS2 - ZX81/TS100 Keyboard adapter over in this thread:
http://forums.parallax.com/forums/default.aspx?f=5&m=145067
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Don't visit my new website...
I found a TS1000 site with a BS2 interface for a keyboard via a serial interface. I prompted the designer to post his code and schematics.
Thanks.
My dad brought home an Apple II plus with extended memory of 64K and we were in awe of its power. User friendly computer languages and point-n-click shortcuts are become so run of the mill that to consider actually KNOWING your stuff is virtually unheard of.
Example - I am learning LISP, my brother in law likes to work on the computer and can do a considerable amount, but when it comes to him understanding why things happen or how to use error handeling he goes nuts. Add to that he knows, at best, part of VBA and he is considered a "computer geek". Truth is if you learned things about programming back when there wasn't a debugger or learned with a language that tells you theres a probelm but doesn't identifiy what, your grasp of computers is significantly better. In my opinion.
In some ways I miss the days of having to label every line of code and needing to think, on the other hand it was very frustrating at times. Basically you don't really have to think with a lot of the most user friendly languages and those who actually program where you have to think are told it must be really hard.
Post Edited (AIman) : 9/23/2006 4:30:01 PM GMT
I'm here because modern computing isn't really that much fun anymore. It pays the bills, but that's about it. --time to start the computing hobby aspect of things again.
I got started on a TRS80 Model I. Wrote elementary BASIC programs to calculate things, like propagation windows for radio. My mentor was a HAM radio operator, who introduced me to electronics and computers at the same time. The model I was a neighbors machine, and it didn't take long until I had to have my own. I eventually got an Atari 400 and tricked it out with real keyboard and 48K of RAM. A good friend ended up with a CoCo 2, also expanded to 64K. We both had cassette drives for the longest time. On that note, the CoCo cassette driver software was the best. It was extremely tolerant of speed changes and supported filenames, and was quite fast. The atari cassette was much worse, but fairly reliable as long as one used the older thicker tapes. (C15's and C30's were the very best at normal bias formulation)
Wrote a bunch of stuff in BASIC, largely games, but a few HAM radio oriented things too. Speed became an issue real quick, also games brought with them some pressure to more fully understand the machine. I wanted to be able to make my computer do those things!
So the assembly language journey began. First 6502, then 6809. The latter was quite likely the most powerful and elegant 8 bitter ever made. (Apologies to you Z80 folks here!) I flunked out of a drafting class in High School because I was flowcharting and diagramming data structures for assembly language programs instead of drawing chain links! Funny, that today a significant part of my professional job involves training people in the finer points of MCAD! Anyway, having the large paper space was just great for sorting out all the little details. Binary graphic objects, storage, program flow, memory map, etc... One C sized sheet of paper could hold, the graphical representations, plus code snippets, and some logic.
Frankly, I loved that time more than any other. It was possible to completely understand the inner workings of the machine. Somebody here mentioned COMPUTE! magazine. I'd like to add Creative Computing and BYTE! to the list as well. It was possible to learn the core elements of computing from rags available in your local grocery store! For a small town kid like I was, this changed my life. If one followed the lessons presented in those publications, in the form of demos games and other type in applications, one earned a fair knowledge of computing.
I'm sure everyone here understands the feeling of getting your first assembly project right. My first one was done totally by hand, on paper. Looking up the OPcodes in the 6502 data book, calculating branch offsets, figuring out where data should live and where it can live. It's amazing that any of us actually got our start at all. Who would spend a week laying out a program that could easily crash and burn in less time than it takes to blink an eye?
I found learning binary numbers very interesting and educational. The most difficult part of low level programming is learning that computers really only do two things: add numbers together and move them around. A real world representation is exactly what you think it is! Putting hello world onto your television really comes down to understanding the machine in use, then making your choice as to how best represent hello world in a manner that when evoked, others will understand!
As I progressed through my career, I ended up doing a lot of hands on manufacturing. (Prototype mechanic in precision sheet metal) Loved the work and NC programming was lots of fun --similar to working with the 8bitters actually. Started with that, the same way I did early computers. Mapped out what needed to happen, then wrote code for each piece. IMHO, this is a skill somewhat lost today. I think it still has value.
When I once again entered into computing for professional reasons, it was on SGI IRIX machines. Nice, beautiful UNIX boxes that had lots of high-end functionality and an elegance that really attracted me. Still use an O2 to this day, as a matter of fact. That time has now gone, leaving us mostly with bland PC's that largely run win32 OSes. No fun at all. --Enter Linux and OSS in general.
One thing that struck me as being obvious in the early times was the open nature of things. If you wanted to learn about something, you looked at it. Disessembling games to understand how they did things was easy. --Often you could just read it right off the disk and go from there. Make some changes, boot the thing and see what happened. Of course that did involved defeating copy protection, but was well worth it, IMHO. Linux / OSS is that way today and it's just about the only thing that makes modern machines fun. Professionally, I've a win XP laptop that I use to teach MCAD and support engineering data management systems on, but somebody else paid for it. My own personal machines are the Atari 400 (yes it still works!), coupla SGI machines from e-bay, and a PC running Ubuntu. I'm not missing anything.
Somewhere in the last few years, the nostalga bug ended up biting. Found myself programming classic 8bit machines again, via emulation. Somebody wrote a compiled basic for the atari 2600 and I've toyed with that plenty. (Wonderful old hardware in that the display system is completely software driven. The smarter you are, the better the display is. New techniques are still being discovered 30 years later!)
I'm here, getting ready to order a prop demo board, from an off hand comment made on one of the classic computing forums. Took one look at the prop and realized it's gonna be just as much fun as the old 8bitters was. Way back when, I used the Atari I/O ports to control things. (fried a coupla of them too.) There was little overhead in that environment and that's where the appeal is. One can blend hardware and software together to do something, without a lot of expense or hassle.
Having caught up with the forums here, with this thread in particular, I realize I've been missing out. No time like the present to get started again! The open nature of this community, that surrounds the parallax product offerings, is just great. (Hope you guys can keep it up, because I think it's gonna suck in a few younger people, who would not otherwise get the same experience through more mainstream means.)
Thanks for the memories, I'm sure this thread will continue to grow. It's just too good of a time to not.