Single-Chip Solution??

Svengali

I am new to the BS. I currently have BS Rev D (1993 ) ·board that I'm playing with. It is a neat system and an easy way to learn MCU programming. The BS is ideal for most of my apps as·I usually don't need a lot of extra I/O. I would like to use this chip in more of my applications; however the problem that I have with it is that it is a two-chip solution since it does not have on-chip flash memory. I would like to be able to program the mcu and just plug it in my application. Is there such a Parallax solution?
·
Sven
·

Bruce Bates

Sven -

I know of no way that the EEPROM can be eliminated from any Parallax PBASIC STAMP configuration. It's inherent in the system design that a EEPROM be there. I suppose some future product might have on-board flash memory, but not at the present time.

Regards,

Bruce Bates

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
When all else fails, try inserting a new battery.

allanlane5

"Two chip"? Any processor you're going to use has a resonator/oscillator, probably a linear regulator of some description, some interface hardware to program it. The BS2 flavors add a brown-out reset detector.

However, the BS2 DOES come in a single 24-pin wide-DIP form-factor, is that good enough?\

Having said that, check out the SX48 family -- Parallax sells that, and that IS a "one-chip" processor with on-chip flash memory. You'll still have to add an oscillator, though. Or, just buy the $10 SX48 board. You'll need the $100 development system to prototype with, though.

Capdiamont

With the SX proto board, you do not need the "$100" development system, you can get away with just buying the sx key for $50 or blitz for $30. The blitz doesn't have debug though.

The sx does have an internal clock, if you don't need accurate clock, or above 4mhz speed. You do need accurate clock to deal with serial comms. It also has built in brown out detection.

allanlane5

Okay, so you save a WHOLE $20, but you lose debug capability. I don't think it's worth it, personally, plus the kit includes some very nice reference books AND a couple of chip and resonators to practice with. Besides, the kit also has a nice prototyping area.

Svengali

Allan, I guess I should clarify·that I mean·the processing/memory solution. I·don't count the other items you mention as part of the solution. The power supply (regulator) is need·by other parts of the hardware; the others are passives that are needed by any·MCU design. The programming/debug hardware is also need for all MCU programming where integrated or as a separate hardware. These days with the ubiquity of MCUs with on-chip flash there should be no need to put an extra chip on the board for simple compact designs. In fact, the PIC16F54 is a drop in replacement for the BS chip with on-chip flash.·That's a neater solution, and could be another option that they offer.
·
I have an application right now where·all I would need to do is drop in the BS, but·now I have to consider the EEPROM. As designs are getting more compact, board space and power are becoming a premium. This is common practice, so Parallax must have a reason for not doing this. But it would be nice, and might open the BS to more applications. It should not be hard to modify the current programming and SW. But, I could be wrong. Perhaps it's in the·works. Just saying it out loud...

Mike Green

You need to understand that the BS2 (and BS1) use processors with built-in flash EEPROM and use that to store the Basic interpreter which fills the flash memory. The external EEPROM holds the interpretive code for the compiled Basic program. You can certainly use a PIC16F54 and program it using one of the 3rd party Basic compilers available. The newer Stamp models use the SX processor and you can program that using SX/B which is a Basic compiler using the SX-Key to do the downloading, but then you don't have a Parallax Stamp and you don't have the same debugging tools and it's not as easy to use and the Basic language accepted by the compilers is not quite the same as that handled by the Stamp compiler/interpreter.

Similarly, the Propeller requires the use of an external EEPROM. In this case, there's masked ROM on-chip that holds the bootloader and Spin interpreter along with some useful data (display fonts and transcendental tables). The processor chip is made using a manufacturing process that doesn't allow the use of flash memory, so that's simply not available.

Post Edited (Mike Green) : 11/23/2008 5:51:33 AM GMT

Svengali

Mike, I get what you are saying. No doubt, the simplicity is really a great. I think it's the easiest way to learn MCU programming. I have programmed with Motorola, Microchip, and Zilog MCUs using various tools. The·Parallax is actually the easiest. I remember playing with the BoeBot briefly a·few years·back and I was able to get the thing running in 5 min.· Talk about good out of box experience. It tool me a whole semester to learn to program the 6811·.· So, the BS definiely has that advantage.
·
But, personally, I would like to have the memory on chip for my applications. I understand that the BS has on-chip EEPROM, but as you say it's for the interpreter, and I think it's OTP.
·
Let's take an application·like a keyfob for a simple car alarm; you wouldn't want to have to put down the extra external memory because of space and extra power requirement. The other Parallax solutions might solve this, but the extra unused features and I/O·might be overkill.
·
BTW, why couldn't the interpreter be part of the SW. Also, don't some MCU let you section the flash into a boot section and a program memory section? Don't recall if the PICs do that - it's been a while.
·
Anyway, I really like the BS. I guess I'm just looking for my ideal, simple MCU solution.

Bruce Bates

Svengali -

Have you looked at all the BS-1 solutions? Here is the BS-1 solution that I would probably use, in the OEM configuration:

www.parallax.com/Store/Sensors/CustomKits/tabid/134/ProductID/3/List/1/Default.aspx?SortField=ProductName,ProductName

I'm not sure how you can beat that for ease of programming, size, cost, weight, and reliability. Can you imagine in your wildest dreams that every Motorola, Microchip, or Zilog microcontroller that goes out the door is FULLY TESTED? Every Parallax product IS! Beat that for reliability, if you can!

BTW - When you put interpreter code in software, is is easily subject to tampering, or theft. Parallax values its proprietary systems, and thus puts the code in protected areas. In this day and age mere encryption is hardly enough.

If you have any other questions, please don't hesitate to ask. Technical questions should probably be referred to Parallax Technical Support at their toll free number. You can find that on the Parallax web site.

Regards,

Bruce Bates

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
When all else fails, try inserting a new battery.

Post Edited (Bruce Bates) : 11/23/2008 10:25:51 AM GMT

Mike Green

Again, look at the SX. It can be programmed using Basic (SX/B), is a single chip solution, is cheap. It requires a programmer (SX-Key or SX-Blitz). There is a 3rd party C compiler available as well. You can also look at any of the other single chip microcontrollers on the market from Microchip, TI, Atmel, etc. They pretty much all have either C or Basic compilers available, require some kind of external programmer. You'll notice that they're all harder to use than the Stamps. The C or Basic compiler generally doesn't produce quite as efficient code as you might expect and, if you use any of the "fancy" I/O statements, the generated code (and library routine code) takes a lot of memory. You won't find that you can fit quite as large a program in as you might think just reading the documentation. You may also find yourself having to use assembly language more than you would expect, just to get your program(s) to work.