Question about Homebrew RIB & M1225

aaknitt · Post by **aaknitt** » Wed Feb 01, 2006 1:05 pm

Hi all,

I made a UPI/RIB for programming various pagers and radios. It works fine on Minitor IIIs, various ham radios, and GM300s. When I try to read a M1225, it locks the radio up so that the buttons don't work until power is cycled. If I do the comm test in the RSS, the radio display resets, the radio beeps, but then it locks up and the comm test fails. (see http://batboard.batlabs.com/viewtopic.php?t=45126 )

I'm wondering if the problem is the RIB or if it could be that the M1225 was originally programmed with a newer version of RSS (I have 3.1).

If the problem is the RIB, what would make it work on a GM300 but not an M1225? The circuit I built is virtually identical to the one at http://www.batlabs.com/images/mrib.gif

It would seem that the data link is working from the computer to the radio, since the radio responds. Is that a correct assumption? But the link from the radio to the computer may not be working since the comm test fails? Or maybe the computer to radio link is not working since the radio locks up?

I know I'm in danger of getting a thousands posts that say "buy a real Moto RIB" and I still may, but I'm naturally curious about these things. Do I have a hardware (RIB) problem or software (old RSS) problem? If it's hardware, what might the problem be? Does the M1225 not like the "simulated open collector" of the diode? If I used a true open collector inverting buffer (i.e. 7407) would that help? Any thoughts from the hardware gurus would be appreciated.

Thanks in advance,

Andy

Post by **wavetar** » Wed Feb 01, 2006 5:32 pm

I'd say it's the RIB or cable...RSS version wouldn't matter at all for the 'comms test', and the older version would give a 'codeplug too new' error or similar, it wouldn't lock up the radio.

I have seen some posts in the past which indicated some people had to add a jumper between a couple of pins for the M1225 in order for their home-made cable to work for them. Not sure why, since the factory cable is the same as the Maxtrac/GM300, but I do recall it being posted...either that or it was the GTX...

Todd

aaknitt · Post by **aaknitt** » Wed Feb 01, 2006 6:42 pm

Ah good info, thanks Todd. I'll do some searching to see what I can dig up on jumping pins.

Andy

aaknitt · Post by **aaknitt** » Sun Feb 05, 2006 4:38 am

The only info I've been able to find on a jumper is the bias jumper, which is for the Moto RIBs. The RIB I made is a different design that doesn't need that jumper. Is there a different jumper (radio pins) I should be looking for?

Andy