RTC card problem?

[Doug Arrell]

Hi

I’ve recently assembled one of Stephen Cousins’ Z50 systems and am having issues with the SC505 RTC card. The system consists of SC501 backplane, SC502 Power card, SC503 processor card, SC504 CF card, SC505 RTC card and a SC506 digital I/0 card. Everything works fine without the RTC card, and even with the RTC card and no battery - the boot screen reports the RTC is installed at #0C as expected. When I add the battery it boots fine but once I set the time and date with RTC it is unable to exit the RTC application and if I power down and up it refuses to boot until I remove the battery.  Anyone have an idea what’s wrong?

[Steve Cousins]

That's very odd. I've not seen anything like that before.

Does RTC hang at the point you press "S" to set the time or does it continue to function until you select exit?

If it hangs at "S" then it sounds like a fault with the data or write signal to the DS1302, but I can't think how that would cause it to fail as described.

Another possibility is it writes to the DS1302 in such a way that RomWBW somehow hangs when reading from it - seems unlikely.

I can't think of any really likely scenarios.

Perhaps you could post the terminal output showing RomWBW starting, the RTC being set, and the RomWBW failing to start afterwards. Perhaps there will be a clue there.

I'll think some more.

Steve

[Doug Arrell]

OK, I found out what the issue was. One of the pins on the 50 pin connector had somehow been pushed upwards so that it wasn't connecting to the Z50 bus when the card was plugged in. As soon as I saw it was shorter than the rest, I applied appropriate force to the pin with some pliers and pulled it down, so it was long enough to connect. The card immediately functioned properly as soon as I booted up. Sorry for wasting your time, Steve.