Memory test for Atom?

discussion of games, software, hardware & emulators relating to the Acorn Atom
mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Wed Jun 28, 2017 11:48 am

Thanks Dave,

I'll give that a go next. Night time here, so thanks again for the advice. Let you know how I go with trying the Vic chip.

Matt

User avatar
oss003
Posts: 2550
Joined: Tue Jul 14, 2009 11:57 am
Location: Netherlands
Contact:

Re: Memory test for Atom?

Postby oss003 » Wed Jun 28, 2017 11:51 am

Matt,

I think I found the problem. Your Atom is working ok because if you are running Galaxians from the Software Archive, it needs RAM at #3C00 which isn't installed in your Atom:

galaxians.png

Greetings
Kees

User avatar
hoglet
Posts: 6622
Joined: Sat Oct 13, 2012 6:21 pm
Location: Bristol

Re: Memory test for Atom?

Postby hoglet » Wed Jun 28, 2017 11:54 am

Good spot Kees!

What does this extra code do.

We should definitely try to fix this to be more original.

User avatar
oss003
Posts: 2550
Joined: Tue Jul 14, 2009 11:57 am
Location: Netherlands
Contact:

Re: Memory test for Atom?

Postby oss003 » Wed Jun 28, 2017 12:00 pm

I have no idea but I think the original was from #2900-#3BFF......

User avatar
oss003
Posts: 2550
Joined: Tue Jul 14, 2009 11:57 am
Location: Netherlands
Contact:

Re: Memory test for Atom?

Postby oss003 » Wed Jun 28, 2017 12:14 pm

Matt, can you try this version?

Greetings
Kees
Attachments
GALAXI.zip
(2.94 KiB) Downloaded 9 times

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Wed Jun 28, 2017 12:50 pm

No good folks - Galaxi is crashing once the hires graphics starts - the 00 score appears then freezes.

User avatar
oss003
Posts: 2550
Joined: Tue Jul 14, 2009 11:57 am
Location: Netherlands
Contact:

Re: Memory test for Atom?

Postby oss003 » Wed Jun 28, 2017 12:51 pm

mattd wrote:No good folks - Galaxi is crashing once the hires graphics starts - the 00 score appears then freezes.

This is with the uploaded version?

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Wed Jun 28, 2017 12:57 pm

Yup - the one you post - 2900 CE86 1300
Just another minor detail that may help - Sirmorris metioned when I ordered my AtoMMC whether I was getting one of Phill's ram/rom boards - I assumed yes, but he's busy on another project - there's no clue in that info? He mentioned 'If you have a RamRom on the way then let me know as they system is configured slightly differently'....

Matt

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Wed Jun 28, 2017 12:59 pm

Last update before bed here - it's 11pm - I've salvage a good looking 6502 from a spare Vic-20.
General opinion I should try that? No risk of damage?

Matt

User avatar
oss003
Posts: 2550
Joined: Tue Jul 14, 2009 11:57 am
Location: Netherlands
Contact:

Re: Memory test for Atom?

Postby oss003 » Wed Jun 28, 2017 1:10 pm

mattd wrote:Yup - the one you post - 2900 CE86 1300
Just another minor detail that may help - Sirmorris metioned when I ordered my AtoMMC whether I was getting one of Phill's ram/rom boards - I assumed yes, but he's busy on another project - there's no clue in that info? He mentioned 'If you have a RamRom on the way then let me know as they system is configured slightly differently'....

Matt

That's right, your system is using the IRQ to enter the AtoMMC rom at #Axxx and the AtoMMC controller is now configured to generate an IRQ at break. If you are using Phill's RAMROM board, the system is patched to start the AtoMMC rom at #Exxx by OS which is much more reliable. The AtoMMC has to be configured, not to generate an IRQ at break.

PS Can you upload a video of Galaxians crashing?

Greetings
Kees

User avatar
oss003
Posts: 2550
Joined: Tue Jul 14, 2009 11:57 am
Location: Netherlands
Contact:

Re: Memory test for Atom?

Postby oss003 » Wed Jun 28, 2017 1:48 pm

Another remark, do you have to link the AtoMMC rom to start?
I'm asking this because LK3 is not made and if this link is made, the AtoMMC should start automatically at pressing BREAK or starting *MENU after pressing SHIFT-BREAK.

MMC manual.png

Greetings
Kees

User avatar
oss003
Posts: 2550
Joined: Tue Jul 14, 2009 11:57 am
Location: Netherlands
Contact:

Re: Memory test for Atom?

Postby oss003 » Wed Jun 28, 2017 2:00 pm

I can't find anything strange in Galaxians.
The only thing is that it uses #021C and the variable space #0321-#0385.

There is a way to test this space:

P=#2800;[LDX@#6B;STA#321,X;DEX;BPL#2802;RTS
A=0;LINK#2800
@=0
F.I=65TO90;?#115=I;P.A;N.

A=-1;LINK#2800
@=0
F.I=65TO90;?#115=I;P.A;N.

Greetings
Kees
Attachments
TEST.png

User avatar
hoglet
Posts: 6622
Joined: Sat Oct 13, 2012 6:21 pm
Location: Bristol

Re: Memory test for Atom?

Postby hoglet » Wed Jun 28, 2017 2:19 pm

Kees,

I just checked the version of GALAXIANS and ASTROBIRDS in the archive. Although the file extends to #3CEC, what's above #3C00 is just junk, and is never executed. I have verified this in Atomulator.

In trying to verify this, I found a new Atomulator bug...

The "Main RAM" setting is silently ignored if the "RAM/ROM Enabled" setting is enabled. This seems to be by design, but I found it very confusing, as there is no indication from the UI that it's being ignored.

The offending line of code is:
https://github.com/hoglet67/Atomulator/ ... 502.c#L302

This means it's impossible to validate that a program in the archive will run on a standard memory Atom.

I will change this in the next version - for now I just hacked this locally.

Dave

User avatar
oss003
Posts: 2550
Joined: Tue Jul 14, 2009 11:57 am
Location: Netherlands
Contact:

Re: Memory test for Atom?

Postby oss003 » Wed Jun 28, 2017 2:33 pm

You're right, I was also confused when this option was working but IIRC the idea was that if you have a RAMROM board, you've got 32 kB of RAM.
The Main RAM setting was introduced to emulated a standard Atom.

Greetings
Kees

User avatar
roland
Posts: 2808
Joined: Thu Aug 29, 2013 8:29 pm
Location: Born (NL)
Contact:

Re: Memory test for Atom?

Postby roland » Wed Jun 28, 2017 8:35 pm

Just an interrupt. I can't get this out of my head:

mattd wrote:OK, the plot thickens!
On Clear 4, there's a byte (or word!) near the top (see top image) - I assume this is the cursor as more appear as you type? So all good?
However, blind typing the invert code FOR A=#8000 TO #97FF STEP 4;!A=!A:-1;NEXT there's the usual noise as the code runs, but no complete white screen? Strange?
Matt


I tried to reproduce this and the code is fine. It should invert the screen but I think you did not type the STEP 4 when you typed it blind on the Atom. If you leave that out it then it will re-invert the bits at every iteration of the FOR NEXT loop so the screen will remain black, except that you might see two white lines moving from left to right and then on the next graphic line.

Interesting problem although :-k
256K + 6502 Inside
MAN WOMAN :shock:

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Wed Jun 28, 2017 8:39 pm

Thanks Roland, you are correct - I did miss the step 4. Keep forgetting you can 'poke' a word!
Works fine.
Thanks
Matt

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Wed Jun 28, 2017 11:02 pm

Hi Kees,

Yes, I use LINK#afcc to initialise the AtoMMC each time - didn't want to use my bad soldering skills creating a link across LK3!

I'll post a shot of Galaxians crash later, and try that code to this evening my time - about 10 hours away.

Also, just to be clear I do not have a Prime board as yet - but I informed SirMorris I was getting one on ordering my AtoMMC..

Until later - back to work :?

Matt

User avatar
1024MAK
Posts: 6791
Joined: Mon Apr 18, 2011 4:46 pm
Location: Looking forward to summer in Somerset, UK...

Re: Memory test for Atom?

Postby 1024MAK » Thu Jun 29, 2017 8:41 am

mattd wrote:Last update before bed here - it's 11pm - I've salvage a good looking 6502 from a spare Vic-20.
General opinion I should try that? No risk of damage?

Matt

Yes, try your spare 6502 CPU.

Mark
For a "Complete BBC Games Archive" visit www.bbcmicro.co.uk NOW!
BeebWiki‬ - for answers to many questions...

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Thu Jun 29, 2017 10:16 am

All,

Spare 6502 from the Vic-20 made no difference - all fine until running things - crash

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Thu Jun 29, 2017 10:26 am

Hi Kees,

Code runs fine, Galaxian photo not worth it - it just freezes as the Hi-res screen appears..

I'm going to try swaping to zero page ram I think...

Matt

User avatar
oss003
Posts: 2550
Joined: Tue Jul 14, 2009 11:57 am
Location: Netherlands
Contact:

Re: Memory test for Atom?

Postby oss003 » Thu Jun 29, 2017 12:12 pm

mattd wrote:Code runs fine, Galaxian photo not worth it - it just freezes as the Hi-res screen appears..

It could help to see what's displayed before it crashes so I can try to emulated it in Atomulator by stepping through the program.

Greetings
Kees

User avatar
hoglet
Posts: 6622
Joined: Sat Oct 13, 2012 6:21 pm
Location: Bristol

Re: Memory test for Atom?

Postby hoglet » Thu Jun 29, 2017 12:22 pm

This is definitely a strange one. A couple more thoughts.

Did you replace that missing electrolytic decoupling capacitor that Kees spotted earlier?

Can you measure the power supply voltage on the Atom PCB (e.g. across the power pins of one of the TTL ICs).

I'm still thinking this is a RAM problem, but quite a subtle one...

Dave

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Thu Jun 29, 2017 1:06 pm

Hi Kees - the crash is subtly different each time - some times the 00 score appears - just now we got some action but crashes and freezes as per the photos...
Attachments
IMG_3413.JPG
IMG_3412.JPG

User avatar
1024MAK
Posts: 6791
Joined: Mon Apr 18, 2011 4:46 pm
Location: Looking forward to summer in Somerset, UK...

Re: Memory test for Atom?

Postby 1024MAK » Thu Jun 29, 2017 1:09 pm

Carefully examine the board to see if there are any other capacitors missing, or indeed if any are broken, damaged or showing signs of distress. The loss of too many supply decoupling capacitors (those connected between +5V and 0V/GND) may result in random crashes.

Also, rather than just taking the single voltage reading that Dave (Hoglet) suggests, in addition take multiple readings across the board, including on the CPU and selected RAM power pins. All should be between 4.75V and 5.25V.

Can you please list programs that you have tried. Two lists please: those that work okay, and those that crash.

For programs that fail, does it make any difference if the machine is cold, or has been on for an hour or more?

Finally, what test equipment do you have?

Mark
For a "Complete BBC Games Archive" visit www.bbcmicro.co.uk NOW!
BeebWiki‬ - for answers to many questions...

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Thu Jun 29, 2017 1:11 pm

Hi Dave,

This is the point of my failings as a retro collector - no voltmeter in the house! I do have a good friend / contact - have at look at his link http://members.optusnet.com.au/spacetaxi64/ - He's fixed my amstrad 664, an atari 800 and my Vectrex - top bloke! I'll ask him to give the machine a good check.

Thanks everyone for your help - will report back soon.

Matt

User avatar
1024MAK
Posts: 6791
Joined: Mon Apr 18, 2011 4:46 pm
Location: Looking forward to summer in Somerset, UK...

Re: Memory test for Atom?

Postby 1024MAK » Thu Jun 29, 2017 1:25 pm

Cheap multimeters are available for less than £10 / $10. I would not trust a cheap meter for mains voltage or higher voltage testing. But they are okay for general low voltage work (30V and below).

This type: DT830B is often less than £3 / $3

The Vann Draper DT830B (shown on the left) and SOAR 3010 measuring a 1800 ohm 5% resistor Image

Go buy one :wink:

Mark
For a "Complete BBC Games Archive" visit www.bbcmicro.co.uk NOW!
BeebWiki‬ - for answers to many questions...

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Thu Jun 29, 2017 10:55 pm

Alright Mark, you've convinced me. About time I started learning a bit more about diagnosing my beloved machines :)
Of to Jaycar at lunchtime - Melbourne's equivalent of Tandy! Will investiagte the board at the weekend.
Matt

mattd
Posts: 35
Joined: Sat May 27, 2017 3:59 am

Re: Memory test for Atom?

Postby mattd » Fri Jun 30, 2017 9:23 am

Hi Mark,
so here's my new toy - the instructions are in mandarin so that's not a good sign! But it does come up with 1.5v when I put the leads around a 1.5v duracell battery!
Which selection mode should I use - pic below...
Attachments
IMG_3423.JPG

User avatar
roland
Posts: 2808
Joined: Thu Aug 29, 2013 8:29 pm
Location: Born (NL)
Contact:

Re: Memory test for Atom?

Postby roland » Fri Jun 30, 2017 9:54 am

First of all, to measure voltage the red plug of the meter should go into the right socket with µA,mA,V,Ω. The black plug goes into the middle socket with COM.

You can now check the voltage of the IC's. In many cases the 0V is located at the lower left pin and +5V is at the top right pin. The image below probably makes clear what I mean. Pin 1 is often marked with a small dot next to it.

2114A.gif
(2.41 KiB) Not downloaded yet
256K + 6502 Inside
MAN WOMAN :shock:

User avatar
oss003
Posts: 2550
Joined: Tue Jul 14, 2009 11:57 am
Location: Netherlands
Contact:

Re: Memory test for Atom?

Postby oss003 » Fri Jun 30, 2017 9:55 am

You should use the V= option with the black cable in COM (middle) and the red cable in the uAmA/V Ohm (right)

Greetings
Kees


Return to “acorn atom”

Who is online

Users browsing this forum: No registered users and 3 guests