Quote:
Originally Posted by wasyoungonce
Peter do the usual's:
Check SRAM voltage is above 2.8VDC
Continuity check RS232 cable.
Check RS232 IC has not entered sleep mode. See the FAQ's #11 for this.
I replaced a RS232 IC (as well as many others) on David's Gemini so it can be done easily, cheaply, as a Last resort. It's more than likely the IC is in sleep mode.
Brendan |
Thanks Brendan.
I'm getting 2.93 VDC across the CMOS battery. I imagine that is a reasonable result and probably does not warrant any replacement at this stage. I just turned the Gemini on to check that the battery was retaining the date/time/location etc data and it was all there. I also double checked that the PC connection was still failing. Sadly it was.
So what is left is either a sleeping IC or a dud.
I have identified the relevant cap (C21) coming off Pin7 of the IC. The FAQ says the side closest to the IC is negative and that closest to the RJ22 is ground. Does that equate to the positive side for the purpose of my multimeter? I gather the task here is to power up the Gemini and see if I have voltage =~5VDC. Is that it?
Peter