Possible silly question.I have been able to find no data on the 40H244, 40H245, 40H373 part numbers. Given their function and pinout I'm guessing that a 74HC part would be an acceptable substitute?
Thanks again, Jeff From: M100 <[email protected]> On Behalf Of Fugu ME100 Sent: Tuesday, May 1, 2018 9:26 AM To: [email protected] Subject: Re: [M100] SPAM-LOW: Re: New member - question on 'half' alive Model 100 If checking the buffers etc you should see the I0/M line toggle quite quickly after power on and of course the ALE line. If it does not then it is not even starting a proper boot, I feel your processor is OK they are quite robust and well protected by all the buffers. I think you mentioned a click on power-on this could be the remote relay clicking on, it is controlled by M14, this too is a symptom of an improper boot sequence. This part also controls access to the ROM, if it does not initialize correctly the ROM might never be accessed properly. The chip ids look good to start. You may also want to check continuity to the ROM and RAM chips just to make sure there are no cracks in the Address and Data PCB tracks. The quality of the M100 boards is quite low.
