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Full Version: No response from WiModem232 on C-128DCR
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Hi, new user here. I just ordered and received a WiModem232, intending to use it with my C-128DCR. I have a GGLabs Turbo232/Swiftlink clone that I'm using to hook it up.

I'm in 64 mode, using CCGMS, set to 300 baud, 8N1, and am able to receive the power-up messages from the modem just fine. (Looking for router, no router located, Filesystem Ready). However, the modem won't respond to any commands. ATI, AT, etc. don't send back anything.

I tried Desterm 128 in 128 mode, and it behaved exactly the same way. Not sure what I'm missing here?
I have never tried this myself, but as long as the cable is correct then it should work. Can you verify your cable is good? You could try sending a command to the WiModem, like AT*REBOOT to see if the receive line is getting there. I do program and test each WiModem232 before it ships.
(04-27-2020, 07:15 PM)admin Wrote: [ -> ]I have never tried this myself, but as long as the cable is correct then it should work.  Can you verify your cable is good?  You could try sending a command to the WiModem, like AT*REBOOT to see if the receive line is getting there.  I do program and test each WiModem232 before it ships.

I'm using a known-good DB25 to DB9 adapter since the Turbo232 card has a DB9 port. I'm also seeing the same behavior on an old XP-era PC with a real serial port, so I think we can rule out the Turbo232.

For fun I also tried a USB-to-serial cable on my modern Linux PC--same results.

All I can think of is the modem not liking my adapter for some reason, but I can't fathom why.
Maybe the adapter is bad or perhaps has some pins jumpered that are interfering with other pins? Do you have a DB-25 based RS232 interface or cable? Make sure you are not using a NULL modem adapter or cable. That will never work. You need a modem cable or adapter.
(04-27-2020, 11:43 PM)admin Wrote: [ -> ]Maybe the adapter is bad or perhaps has some pins jumpered that are interfering with other pins?  Do you have a DB-25 based RS232 interface or cable?  Make sure you are not using a NULL modem adapter or cable. That will never work.  You need a modem cable or adapter.

It's not a null adapter. I last used it to hook up a PC with a modem with a DB-25 port using a modem cable.

I'll order a DB-9 to DB-25 modem cable just to be safe. Weirder mysteries have happened with retro gear.  Big Grin
Like I said before, I program and test these before shipping. The programming is actually done on my Amiga 1200 using a terminal program, so both transmit and receive have to work or I can't program it at all. I also test the wireless connection and format the filesystem (there is 3MB of available storage space that will be accessible remotely with a future firmware update).
Works fine with the new cable I got. The weird thing is, that adapter works fine with a real modem I have. Curious. But at least this is working now. Thanks for your help!

The file system access would be pretty cool indeed! Looking forward to that.
Glad that it is working. There must be something in that cable (like RTS, CTS, DTR, or DSR) that is different from the new one you have that works. I know a LOT of cables tie some of the handshaking pins together. You need to be using a complete 9 pin or 25 pin pass through. It's usually the DB9 to DB25 cables that tie the handshaking lines or DCD line.