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Re: CST Thor 1
Posted: Mon May 22, 2017 9:27 pm
by dilwyn
bagpuss22 wrote:Thanks dilwyn, I think I have most of the info from your site.
One thing I have got, that you might like is V4.22 of the Thor ROM.
Russ
Thanks Russ. If you could send it to me as a zipped file, I can upload it to the temporary QL Homepage.
Re: CST Thor 1
Posted: Mon May 22, 2017 10:53 pm
by bagpuss22
HI Dilwyn,
It is attached here
Re: CST Thor 1
Posted: Tue May 23, 2017 8:53 am
by dilwyn
Thanks Russ.
Re: CST Thor 1
Posted: Tue May 23, 2017 11:45 pm
by bagpuss22
@Dave.... Just a quick thought, from your comment!
Could my issues be caused by a faulty ZX8301? RAM management.
I know they can be damaged by plugging in a RGB monitor.
I am seeing the test pattern on boot up but then I have issues displaying the ROM info and
also the ROM checksum fails and I know the ROM is good.
Russ
Re: CST Thor 1
Posted: Fri May 26, 2017 12:36 pm
by bagpuss22
Dave wrote:Do you have a copy of the Thor manual around there somewhere? I know it says something about this.
It could also be a problem decoding addresses so the ROM content is valid but the ROM addressing is faulty, so it reads mush?
@Dave,
I don't have a manual unfortunately.
I am not sure as it seems to read the ROM contents ok 'ish as it displays the ROM names at the boot page. It only seems to have issues with
the CST Thor ROM (which has a checksum facility) and the serial ROM.
I was wondering about the RAM management as sometime the display is not 100% correct with info in different places and would the ROM
checksuming be done in RAM too... Maybe a ZX8301 issue?
It says to disable the RAM on the expansion board by shorting pin 9 of the PAL, which I did, buit that made no difference.
Russ
Re: CST Thor 1
Posted: Fri May 26, 2017 10:01 pm
by Dave
Is there a bent pin in the expansion connector by any chance?
Re: CST Thor 1
Posted: Sat May 27, 2017 1:14 pm
by bagpuss22
OK, todays unhappy update.
Yesterday a new PSU and a pair of NOS ZX8301's arrived.
To start with, there are no bent pins on the expansion connector.
Neither the new PSU or the replacing of the ZX8301 helped
The issue remained the same...
BP
Re: CST Thor 1
Posted: Sat May 27, 2017 7:53 pm
by Dave
Time to whip out the logic analyzer. :/
I have a USB one. It's a nicer one, but 16 channel @ 16MHz can be had cheaply for around $75.
Re: CST Thor 1
Posted: Sun May 28, 2017 9:51 am
by Martin_Head
I've no experience of the Thor. But looking at your photo's, It looks like a fairly standard QL motherboard. Could you extract it and test it separately. It would at least tell you if the problem is on the QL, or the THOR side.
You say you get the checksum error after the CST Thor line. Which on your photograph, is just before the message about resetting the clock. Could you have a problem with the clock?
Martin
Re: CST Thor 1
Posted: Sun May 28, 2017 1:58 pm
by bagpuss22
Martin_Head wrote:I've no experience of the Thor. But looking at your photo's, It looks like a fairly standard QL motherboard. Could you extract it and test it separately. It would at least tell you if the problem is on the QL, or the THOR side.
You say you get the checksum error after the CST Thor line. Which on your photograph, is just before the message about resetting the clock. Could you have a problem with the clock?
Martin
Hi MArtin,
It is my intention to take the QL motherboard out and test it separately.
The CST Thor ROM contains the ROM checksum test and the setup for the RTC. If the ROM is ok then it will go
onto the RTC. SO looking at what I am seeing it is not getting as far as setting up the RTC.
Russ