Troubleshooting an IOM 140/141

jefm

Hey gang,
I bought three IOM's for a project last year and finally got around to building it. I'm not sure if they are 140/141s. These are boards with relays on them built by Peter Anderson that can be operated with serial commands.
Peter has been great helping me in e-mail but before I waste more of his time I was wondering if anyone had used these. I have not even connected to my Stamp yet, I wanted to see it work via a windows pc and Hyperterminal. It does not seem to be responding to commands from the computer. I've tried all types of cables and power supplies, I really think I'm just missing something simple.

I'm using a 12v/500mA/center positive power supply. The serial cable is the same one I use for programming Basic Stamps and connects to a Win2000 machine running Hyperterminal (9600/8/N/1, no flow control). I'm using a Fluke DMM to monitor relay one. When powered up, the "heartbeat" LED blinks every ~10 seconds. When I send commands, sometimes it has a longer blink. But none of the relay LED's ever turn on and the relays do not change state.

Anybody ever mess with these units? Thanks for any help!

PJAllen

When you're sending commands are you using capitals in accordance with his examples?· It's likely case sensitive.

N1   ' operate relay 1
N3   ' operate relay 2
F1   ' turn off relay 1
N4   ' turn on relay 4
F0   ' turn off all relays
N0   ' turn on all relays

Phanderson also·notes that you should get a status response on your terminal.

jefm

Thanks for the reply PJ, I actually got it working by setting the baud rate to 2400 instead of 9600. I cannot get the state of relays or inputs, but am probably going to quit while I'm ahead and just use the relays.

PS, FYI-the commands do not appear to be case sensitve; n1==N1

PJAllen

"...I actually got it working by setting the baud rate to 2400 instead of 9600."

Oh?

Well, all his site stipulates is 9600, 8N1.· Is it "autobaud"?· Looked like that page there was as much documentation as he makes available online.· Does he send more with the unit?·
Did you buy a kit or some other or a finished unit?· Is it phanderson's cable or your own?

jefm

Hello PJ,
I'm not sure about autobaud, all I know is the relays respond at 2400 bps, I quit experimenting after that [noparse]:D[/noparse]
To be honest, I bought these a long time ago and got lazy on my project, if they came with any extra direction they are long gone.
I'm using same serial cable I program the stamps with (USB does not seem as reliable with "bigger" programs)
Although I tried a bunch of cables/power supplies.

Ultimately PhAnderson graciously offered to send me a new CPU for the IOM so I assume I have an old version that is not congruent with the instructions posted on his site.

Thanks for the help gang, this problem's almost kicked :}