Does the RTC drive an interrupt to service the KB? Interesting I did not realize that.
Jeff Birt From: M100 <[email protected]> On Behalf Of Stephen Adolph Sent: Friday, April 23, 2021 4:56 PM To: [email protected] Subject: Re: [M100] Dead Keyboard I suspect that there is a problem with the internal real time clock. I would check if there is a pulse on pin 10. Hard to verify that I will admit. Basically, pin 10 is the timer pulse on the RST7.5 input to the processor. If you have a problem here your keyboard service routine will be "dead". To me it sounds a bit like a dead x1 crystal at pin 12/13 of the real time clock chil. On Fri, Apr 23, 2021 at 5:40 PM John R. Hogerhuis <[email protected] <mailto:[email protected]> > wrote: On Fri, Apr 23, 2021 at 1:44 PM Matthew Walworth <[email protected] <mailto:[email protected]> > wrote: Thank you for pointing me at that document, John. No luck with the procedure fixing the unresponsive keyboard, although it did bring to my attention that there is a slight glitch in the upper left corner of the LCD. When first turned on, where it should show "Jan" it shows three other characters. After being on for a few seconds the "Jan" display appears. I also just realized that the clock doesn't start counting up after the reset. It should shouldn't it? Yes. After a hard reset it should start up in Jan almost immediately (I think seconds later is significant problem), and the clock should start counting up. -- John.
