$3.00 programming cable hack?
Oldbitcollector (Jeff)
Posts: 8,091
I'm always on the lookout for ways to lower the "price of entry" for new folks
getting into the Propeller. I came across this article in my RSS feeds this morning.
I'm curious if this *might* be an alternative for our Prop-plug as well?
www.uchobby.com/index.php/2009/10/04/diy-usb-to-serial-cable-for-3/
Perhaps those who are a bit more EE' knowable than I could look and answer.
OBC
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New to the Propeller?
Visit the: The Propeller Pages @ Warranty Void.
getting into the Propeller. I came across this article in my RSS feeds this morning.
I'm curious if this *might* be an alternative for our Prop-plug as well?
www.uchobby.com/index.php/2009/10/04/diy-usb-to-serial-cable-for-3/
Perhaps those who are a bit more EE' knowable than I could look and answer.
OBC
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New to the Propeller?
Visit the: The Propeller Pages @ Warranty Void.
Comments
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lt's not particularly silly, is it?
Good find. It looks like the CA-42 should work great. You would want to implement the optional DTR hack toward the end of the article. Also assuming that the Parallax software treats the interface as only a serial device and does not toggle DTR using FTDI specific methods.
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James Ronald
My Robots
FTDI also make cables which can be used (provided you add the transistor reset circuit) but they are $20.
You can buy PC USB to Serial RS232 adapters for about $6 including postage but will need to use a circuit to restrict the voltage (transistor circuit) and of course the reset circuit as well. Still a cheaper solution and maybe you already have one in the junk box.
BTW Just about everyone has a USB to mini-USB cable for a camera or phone these days, so we just have to find a cheap USB chip to do this. The FTDI chip is $4.50 which is expensive. There must be a cheap pic solution somewhere???
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Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade, RetroBlade,·TwinBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: Micros eg Altair, and Terminals eg VT100 (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm
Post Edited (Cluso99) : 10/6/2009 1:04:44 AM GMT
The Propplug is a ready-made solution..
Here's an additional link dealing with the same topic.
buffalo.nas-central.org/index.php/Use_a_Nokia_Serial_Cable_on_an_ARM9_Linkstation
OBC
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New to the Propeller?
Visit the: The Propeller Pages @ Warranty Void.
It does work but you be the judge if this is for you.
Bought my cable from here: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=370185543289 , photo attached of what it looks like when you rip the blue plastic cover off of the USB side
Problem 1: The cable came with no drivers, downloaded the drivers from the Prolific site, these did not work. Did a Google search and found a post on microsoft.com that had a link to some older drivers, installed these and now Vista is happy. Installed on COM 8. Tested the cable with RX and TX looped back to each other using a terminal program (ProComm). Whatever was typed was echoed back.
Problem 2: The cable going to the 'Phone' is only 3 conductor (RX, TX, & Ground), so I removed the cable and installed a 4 pin header, so I could plug the whole adapter into a bread board and the connect the USB to serial adapter to the notebook with a USB extension cable.
Problem 3: you'll have to add the attached circuit (copied from this schematic: http://www.parallax.com/Portals/0/Downloads/docs/prod/prop/proprpmv10_schema.pdf) This completes the DTR to RES connection to the Propeller so the Propeller Tool can program the chip.
With all the above work you now have a working Prop Plug based on a Prolific PL-2303 USB to Serial device.
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Mike
Post Edited (Mike Cook) : 10/10/2009 12:44:39 AM GMT
Also, RTS can be set to be pulled low along with DTR.
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Hey! I'm Adam.
But YOU can call me ziplock.
Blog: braindrink.wordpress.com
"The only problem with the gene pool is that there is no lifeguard." -David Gerrold
If I had the time I would find a PIC or Freescale solution to replace the FTDI chip - I am sure it could be done with a <$2 chip and we could then make a real cheap propplug pcb.
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Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade, RetroBlade,·TwinBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: Micros eg Altair, and Terminals eg VT100 (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm
This what I thought of, but I don't think the licensing is suitable.
http://www.obdev.at/products/vusb/index.html
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Style and grace : Nil point
Post Edited (Toby Seckshund) : 10/10/2009 8:40:30 AM GMT
(And my ex-skip 19" monitor has just booked a return journey)
More hunts have not found them. Hey ho.
If only there was an eight pin DIP ft232 (and a 84 pin PLCC prop
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Style and grace : Nil point
Post Edited (Toby Seckshund) : 10/10/2009 6:16:15 PM GMT
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Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade, RetroBlade,·TwinBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: Micros eg Altair, and Terminals eg VT100 (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm
If only there were just six more winning numbers on my lottery ticket, last night.
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Style and grace : Nil point
Here is a cheap $3.50 USB to Serial cable that was hacked...
It even works...
http://i385.photobucket.com/albums/oo298/fsafstrom_2008/100_1111.jpg
http://i385.photobucket.com/albums/oo298/fsafstrom_2008/100_1114.jpg
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Living on the planet Earth might be expensive but it includes a free trip around the sun every year...
Experience level:
[noparse][[/noparse] ] Let's connect the motor to pin 1, it's a 6V motor so it should be fine.
[noparse][[/noparse] ] OK, I got my resistors hooked up with the LEDs.
[noparse][[/noparse]X] I got the Motor hooked up with the H-bridge and the 555 is supplying the PWM.
[noparse][[/noparse] ] Now, if I can only program the BOE-BOT to interface with he Flux Capacitor.
[noparse][[/noparse] ] I dream in SX28 assembler...
/Bamse
Get the Nokia cable described above...
Take it apart and add a 2N2222 or similar NPN Transistor, 2x10K (Brown Black Orange) resistors and a 10nF (103) cap.
Put a header on the ribbon cable and mark the "up" side.
Flat side up, solder the two resistor to the Base and Emitter.
Hook up the ribbon cable.
Collector goes to Reset on ribbon cable and add a ground wire to Emitter...
Add cap to the resistors and the DTR on the plug.
Make it fit in the case...
Lid on...
Hook up to Propeller...
And test it...
See, that wasn't too hard...
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Living on the planet Earth might be expensive but it includes a free trip around the sun every year...
Experience level:
[noparse][[/noparse] ] Let's connect the motor to pin 1, it's a 6V motor so it should be fine.
[noparse][[/noparse] ] OK, I got my resistors hooked up with the LEDs.
[noparse][[/noparse]X] I got the Motor hooked up with the H-bridge and the 555 is supplying the PWM.
[noparse][[/noparse] ] Now, if I can only program the BOE-BOT to interface with he Flux Capacitor.
[noparse][[/noparse] ] I dream in SX28 assembler...
/Bamse
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Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm
I've been thinking about an alternative to the Prop-Plug for a bit. I think the Prop-Plug is a real obstacle to entry and seriously increases per-seat costs in classroom environments.
The page you noted looks interesting, I'll have to read it. At first glance looks like they're using an ATMega328 with a bootloader and someone's USB stack.
I have seen USB/Serial (USB/i2c too) done in the likes of the ATtiny45, which at around $2 USD in unit qty is perhaps cheaper. But I know of no zero-royalty third party bootloader/USB-stack solution for AVR if you wanted to sell these things. These folks:
www.obdev.at/products/vusb/index.html
...have a nice USB stack for AVR micros. I seem to remember it is free for non-commercial use. Their commercial license is $1.33 per instance for maximum 150 units. Then there's a virtually unlimited license for a flat $500. You get a unique VID/PID pair with each commerical license.
For about $3 in unit quantity, you can use an AT90USB162. This is a nice AVR micro that has a factory pre-programmed USB stack with bootloader/programmer. This part would make a real nice prop-plug in my opinion, and at a lower cost that the ATtiny45 with the above mentioned license fee. Not only that, but you can use it as a general purpose USB bridge (i2c, SPI, etc.), a sniffer, general-purpose micro-controller (lots of I/O), or maybe even program it to be some sort of Propeller in-line debugger.
Oh yes, the Object Development USB stack mentioned above has a self calibration routine that allows you to do the USB bridge without a crystal. The AT90USB192 needs an 8MHz crystal (typical frequency, about $0.20 each) or resonator as long as the stability is 8MHz X 15 = 48MHz +/- 0.25% where 48MHz is the USB clock after the external crystal or resonator 16 times PLL multiplier.
With my suggestions, in small quantities you're not going to end up at $3 a cable. But I would think it wouldn't be too much more; certainly a lot cheaper than the Prop-Plug. I really like the AT90USB162 solution, it's kind of like the Swiss army knife of USB bridges.
Regards, David
Too slow.
<EDIT> sorry, I should elaborate.
Firstly their USB stack has no protection against data corruption as it ignores the packet CRC's.
Secondly it uses low speed usb which is limited to an absolute maximum of 1000 packets per second at 8 bytes a packet (if the AVR could keep up, which it can't).
Low speed USB is why I tossed in the work on my USB bootloader. It's just *soo* much faster (and I mean really) loading a prop with a serial port vs on-board USB.
In this case, your AVR bridge would fail as the Prop tool would try and configure the port at 115200 baud (which the driver will subsequently ignore) and chuck the data out so fast your device will run out of buffer space and start dropping bytes.
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lt's not particularly silly, is it?
Post Edited (BradC) : 10/21/2009 2:22:02 PM GMT
Love the hack. It works !
That is all I need.
I love small hack projects like this, sometime you just don't have what you need around the shop to get projects up and running so what do you do ?
Make it work with what you have.
Projects like this always keep me going !
Thanks for sharing.
Rob 7
I really hope it would be the opposite, people see the cheap programming device and decide to get going with the prop...
Like the spirit this thread started out with...
Would it be a good idea to move this hack itself to the "Completed Projects" forum ?
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Living on the planet Earth might be expensive but it includes a free trip around the sun every year...
Experience level:
[noparse][[/noparse] ] Let's connect the motor to pin 1, it's a 6V motor so it should be fine.
[noparse][[/noparse] ] OK, I got my resistors hooked up with the LEDs.
[noparse][[/noparse]X] I got the Motor hooked up with the H-bridge and the 555 is supplying the PWM.
[noparse][[/noparse] ] Now, if I can only program the BOE-BOT to interface with he Flux Capacitor.
[noparse][[/noparse] ] I dream in SX28 assembler...
/Bamse
The kind of person who would build this will buy many other things (Propellers, protoboards, etc. etc) from Parallax. [noparse]:)[/noparse]
I'm really pleased to see this hack work... @Bamse do you mind if I move a copy of this
over to Warrantyvoid and post a link to something like Hackaday? I'd love to see this
get some attention and bring in a couple more propellerheads.
OBC
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New to the Propeller?
Visit the: The Propeller Pages @ Warranty Void.
I'll post a copy of this hack in the completed forums later tonight, I want to add a few more details to make it easier for those who want to build one.
So you might want to hold off the copy until I have moved it over to the Completed Forum...
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Living on the planet Earth might be expensive but it includes a free trip around the sun every year...
Experience level:
[noparse][[/noparse] ] Let's connect the motor to pin 1, it's a 6V motor so it should be fine.
[noparse][[/noparse] ] OK, I got my resistors hooked up with the LEDs.
[noparse][[/noparse]X] I got the Motor hooked up with the H-bridge and the 555 is supplying the PWM.
[noparse][[/noparse] ] Now, if I can only program the BOE-BOT to interface with he Flux Capacitor.
[noparse][[/noparse] ] I dream in SX28 assembler...
/Bamse
Bamse you should sell these as a kit I bet they would be very popular thanks again
Thanks for the reply. I have a gut feeling there is depth of knowledge in your reply to my post.
When you say, "their USB stack has no protection against data corruption as it ignores the packet CRC's..." etc., are you referring to the ObDev V-USB stack and/or the pre-programmed stack in the AT90USB162?
Rgds, David
Drone: Once the chip costs $3 + other components, the FT232R comes into it's own at $4.50. It is an expensive smt chip for the volume but it's so simple.
I worked out a way to break the tracks on the Prop ProtoBoard USB into 2 headers so it can be used as a standalone Proplug as well (and fixes the reset problem by using a removable header plug/shunts. OBC - do you still have the details??
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Links to other interesting threads:
· Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm
I was referring to the ObDev stack actually. The AT90USB162 has a hardware USB controller and is capable of full speed operation with up to 64 byte endpoint transfers.
You *could* in theory actually program that device to emulate the FTDI chip. The Hardware USB controller is pretty similar to the one available in the PIC's although it is limited to 4 endpoints.
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lt's not particularly silly, is it?
I really don't quite understand why the cap has to be there, since all the voltage are the same. So in desperation I just connected the DTR directly up to the RESn pin. And that does cause a reset when DTR toggles. Am I going to burn up something doing this? I tried putting a series resistor (about 2K) in line, mainly because it was handy, but that prevented the reset too. Only thing that works is a direct connection.
But even with it now resetting when the DTR toggles, the Propeller Tool still does not recognize a propeller connected to the virtual COM port. It causes a reset (which I think it is supposed to do), but always fails saying it can't find a prop on any COM port (this is the only COM port available).
By swapping the capacitor for a larger one (.47uf vs .01uF) the reset takes place like with the direct connection. Propeller Tool still doesn't recognize it....so I thought..
But now, if I remove and reinsert the USB device, the Propeller Tool will find and program the Prop......but only once!! It will always fail every time after that. Everytime I remove and reinsert the USB device, it works.
some time ago i did a programmer out of a chinese nokia cable.
It works great althought i did just connect the signals strait from the USB<->Serial chip to the Propeller programmin connector (Res = DTR).
I only had to put a small capacitor on the Rx line (if i remember well). Some kind of retarding.
The chip is a PROLIFIC one ...
...
...
I whish all problems were so easy to solve ... !
ciao
Marcello
PS: my cable did it only with the scope probe connected on RX, so i came to the idea that the solution was the capacity of the probe itself. Maybe it works also with less than 0.1uF ...
Post Edited (Marcello) : 11/27/2009 10:44:28 PM GMT
I wouldn't doubt many other first time Propeller customers have actually decided against getting into the propeller for this reason. Now that I can make my own PCBs, I tried making my own PropPlug... The whole thing cost me under $10. I'm sure Parallax has their reasons, but why make the door into Propeller Land so hard to open?