Search found 366 matches

by Boydie
Fri Dec 06, 2019 9:28 am
Forum: hardware
Topic: (Risc PC) Repair of a lever from the tray cover...
Replies: 2
Views: 103

Re: (Risc PC) Repair of a lever from tray cover...

A broken RiscPC case? Surely not! When they launched it, Acorn said it was incredibly tough and made out of the same material as riot shields. :lol:

Makes you feel really sorry for mid-90s riot police, if that’s what they were defended by...
by Boydie
Sun Dec 01, 2019 3:51 pm
Forum: hardware
Topic: Another dead A4 (resurrected)
Replies: 11
Views: 480

Re: Another dead A4 (resurrected)

Well, in a major break with tradition, the repair not only worked but has done so first time! Isn't that one of the signs of the apocalypse? At first the HD looked like it had died from the shock, but a quick thump of the "it's dead anyway, so what have I got to lose" variety seems to have unstuck i...
by Boydie
Sun Dec 01, 2019 9:16 am
Forum: hardware
Topic: (HELP) RISC PC & the black screen of Doom... :-(
Replies: 6
Views: 167

Re: (HELP) RISC PC & the black screen of Doom... :-(

Dying hard disk - looks like it’s generating read errors progressively earlier?
by Boydie
Fri Nov 22, 2019 10:13 pm
Forum: hardware
Topic: My BBC B won't boot with a SMART SPI or DFS 0.9
Replies: 26
Views: 691

Re: My BBC B won't boot with a SMART SPI or DFS 0.9

That would be S2. Also make sure S9 is made, otherwise it’ll still be looking for a disc interface that may or may not be there (but may have been in the past).
by Boydie
Thu Nov 21, 2019 7:25 am
Forum: hardware
Topic: Another dead A4 (resurrected)
Replies: 11
Views: 480

Re: Another dead A4

Thanks. I’ve already neutralised the battery gunk with acid and gentle brush scrub, followed by distilled water and ipa. Hopefully all that’s left is residual staining/corrosion that won’t progress. I suspected running wire wrap to the vias was the way to go, and was wondering about doing the same w...
by Boydie
Wed Nov 20, 2019 7:09 pm
Forum: hardware
Topic: Another dead A4 (resurrected)
Replies: 11
Views: 480

Re: Another dead A4

Okay, so all caps removed. A few were a bit ropey and had leaked.
Five pads came off - C19 west, C89 south, C134 both, C65 east. Everything else seems relatively unscathed.

What’s the best way to repair these?
89B24588-A71A-4825-AEB2-E6AA25B5CD25.jpeg
by Boydie
Tue Nov 19, 2019 2:55 pm
Forum: hardware
Topic: Another dead A4 (resurrected)
Replies: 11
Views: 480

Re: Another dead A4

Thanks. I’ll get the caps ordered and report back.
by Boydie
Sun Nov 17, 2019 6:05 pm
Forum: hardware
Topic: Another dead A4 (resurrected)
Replies: 11
Views: 480

Another dead A4 (resurrected)

I think I know what the answer's going to be, but I'm going to ask anyway, just in case before I start... A couple of years ago, my A4 was working. I removed the battery before it could leak and soldered a couple of flying leads in its place. When I reassembled it, it no longer worked. So I boxed it...
by Boydie
Fri Nov 15, 2019 11:21 am
Forum: acorn atom and system
Topic: YARRB [SOLD OUT]
Replies: 274
Views: 17961

Re: YARRB [SOLD OUT]

Is that an otherwise expansion-free Atom? In my case, it appears to work fine (so far as I can tell) with no other expansions fitted - keyboard works etc, and only hangs if AtoMMC is fitted *and* the machine knows about it and tries to use it. Could it be that the W65C02 is more fussy about timings/...
by Boydie
Thu Nov 07, 2019 9:34 pm
Forum: acorn atom and system
Topic: YARRB [SOLD OUT]
Replies: 274
Views: 17961

Re: YARRB [SOLD OUT]

Thanks Dave.
The link options are as I thought. I've tried with both R1 and R2 fitted, and just R1. The result is the same - AtoMMC and the W65C02 just won't play nice together.
I suspect the effort required to get them to do so probably won't be justified by the benefits of succeeding.
by Boydie
Thu Nov 07, 2019 7:20 pm
Forum: acorn atom and system
Topic: YARRB [SOLD OUT]
Replies: 274
Views: 17961

Re: YARRB [SOLD OUT]

Okay, so one "new" crystal later it's working. AtoMMC works fine with either the original 6502 or a spare Model B one. It really hates the W65C02S6TPG-14. Please can someone just clarify the JP4 positions for 6502 vs 65C02? As far as I can tell, the pins aren't labelled, and the various pictures peo...
by Boydie
Thu Nov 07, 2019 12:36 pm
Forum: acorn atom and system
Topic: YARRB [SOLD OUT]
Replies: 274
Views: 17961

Re: YARRB [SOLD OUT]

Now the Atom's died! One minute, it's all working fine. The next, dead as a doornail. I've removed the YARRB and reversed all the changes but still no display and no response to CTRL-G. So I've now got to fix that before doing anything else... Edit: It's not *completely* dead. There's no display wha...
by Boydie
Thu Nov 07, 2019 12:19 pm
Forum: acorn atom and system
Topic: YARRB [SOLD OUT]
Replies: 274
Views: 17961

Re: YARRB [SOLD OUT]

Thanks for the ideas. I've just tried it again, but with the original 6502 rather than the CMOS one. It works absolutely fine - ATOMMC banner and catalogues the card. So it's clearly something the 65C02 is doing that's upsetting things. Please can someone just confirm how all the jumpers should be s...
by Boydie
Thu Nov 07, 2019 11:25 am
Forum: acorn atom and system
Topic: YARRB [SOLD OUT]
Replies: 274
Views: 17961

Re: YARRB [SOLD OUT]

Okay, a bit of progress... LK3 was made. Now I've unmade it, the machine boots with the AtoMMC hardware fitted and SD card inserted. Hoglet's test program shows it can communicate with the AtoMMC hardware. ?#BFFE=6 makes the machine hang after Break, with just the ATOM banner (no mention of ATOMMC)....
by Boydie
Thu Nov 07, 2019 10:17 am
Forum: acorn atom and system
Topic: YARRB [SOLD OUT]
Replies: 274
Views: 17961

Re: YARRB [SOLD OUT]

I've finally built mine. It's 95% functional, first time. I'm using a new W65C02S6TPG (CMOIS 6502, up to 14MHz). I've set JP3 North and JP4 West, and made JP5 and 6. 39SF010A has been programmed with the image from diy.acornatom.nl. It starts up fine, I can select BBC Mode without problems. It won't...
by Boydie
Mon Nov 04, 2019 9:33 am
Forum: hardware
Topic: RiscPC palette weirdness
Replies: 6
Views: 346

Re: RiscPC palette weirdness

It's now not recognising the keyboard that it was quite happy with yesterday. The list of issues is growing, and I suspect it's time to take it down to the bottom of the garden and shoot it. :( I'd still dearly love to know why there's a difference between RO3.5 and later variants in terms of colours.
by Boydie
Mon Nov 04, 2019 7:46 am
Forum: hardware
Topic: RiscPC palette weirdness
Replies: 6
Views: 346

Re: RiscPC palette weirdness

Yeah, resetting the CMOS is the only way I can get it to show anything. Both simm sockets have been tested, right the way from the individual pins, and are fine to both the buffers and the equivalent D pin in the vram socket. I’ve not tested the other pins in the simm sockets yet... Symptoms are the...
by Boydie
Sun Nov 03, 2019 8:23 pm
Forum: hardware
Topic: RiscPC palette weirdness
Replies: 6
Views: 346

Re: RiscPC palette weirdness

This has been a day of *very* tedious tracing. So far, I have found: All pins of D0-D31 have continuity, from the RAM socket, to the relevant buffer IC (22/26/30/33), to the relevant resistor pack (which has appropriate resistance), to the relevant Vcd input on VIDC. Pins 1 and 19 on the buffer ICs ...
by Boydie
Sun Nov 03, 2019 1:35 pm
Forum: hardware
Topic: RiscPC palette weirdness
Replies: 6
Views: 346

RiscPC palette weirdness

I'm trying to fully resurrect a RPC 600 (0197,100) following battery leakage. There are a few issues, probably best dealt with one at a time. The first one is a somewhat bizarre colour palette in RO 3.6/3.7. In RO 3.5, all colours are fine. However, in 3.6 the palette goes seriously screwy: VRAM sta...
by Boydie
Sun Nov 03, 2019 9:21 am
Forum: hardware
Topic: Drive Empty - Citizen OSDC-65C
Replies: 5
Views: 281

Re: Drive Empty - Citizen OSDC-65C

I had exactly the same issue with this drive yesterday. In my case, the motor spun, but the drive in use light on the drive itself never lit up, and the A3000 reported drive empty. There’s a (very) tiny slider for selecting Drive 0 vs Drive 1. This should be to the right as you look at the rear of t...
by Boydie
Sat Nov 02, 2019 5:33 pm
Forum: hardware
Topic: Very dead A3000 (now very much alive)
Replies: 20
Views: 834

Re: Very dead A3000 (now very much alive)

One last fault found - broken trace between L7 and pin 27 of the 8051, which meant mouse Y-axis wasn't working. Now appears to be fully functional - Econet and User Port/MIDI cards are recognised, as is 2Meg RAM upgrade. Floppy drive access works fine. Mouse is fully functional. Even the RTC seems t...
by Boydie
Fri Nov 01, 2019 10:07 pm
Forum: hardware
Topic: Very dead A3000 (now very much alive)
Replies: 20
Views: 834

Re: Very dead A3000

Well, I removed LK 17&18. There was definitely no continuity between LK18 pin1 and the via, but the damage must have been very subtle because there was nothing visible, even with a magnifying glass. Replaced LK 17&18. Patched between LK18 and the via. Got continuity between IOC p66 and IC31 p13. IOC...
by Boydie
Fri Nov 01, 2019 9:28 pm
Forum: hardware
Topic: Very dead A3000 (now very much alive)
Replies: 20
Views: 834

Re: Very dead A3000

I seem to have lost track of where you got to on this repair project. Driven halfway up the wall and at the end of my tether. :) Working my way through the Service Manual... 1) IC13 pin 29 starts low on power-up and changes to high after a second or two. Originally it didn't, but fixing that broken...
by Boydie
Fri Nov 01, 2019 2:44 pm
Forum: hardware
Topic: Very dead A3000 (now very much alive)
Replies: 20
Views: 834

Re: Very dead A3000

Well, my hopes weren't high, and I wasn't disappointed! Changing the 74LS145Ns hasn't helped. I've also swapped out the 32.768MHz crystal because that looked a bit manky. I've also continuity tested all the pins for the ROMs as far as ICs 29-31 for the address lines, MEMC p60 for ROMCS, and the corr...
by Boydie
Tue Oct 29, 2019 11:24 pm
Forum: for sale / freebies
Topic: Acorn Atom software for sale
Replies: 11
Views: 528

Re: Acorn Atom software for sale

Lardo Boffin wrote:
Tue Oct 29, 2019 5:08 pm
Life.
Don’t talk to me about Life. :(
by Boydie
Tue Oct 29, 2019 4:26 pm
Forum: acorn atom and system
Topic: Yarrb - redesigned
Replies: 55
Views: 1921

Re: Yarrb - redesigned

I’m sure there’s a very good reason why not, but would it be possible to design a system whereby the CPLD sits on a daughter card which then plugs into a socket with a sufficient number of pins? Then, when the CPLD becomes obsolete it’s only a matter of redesigning a new daughter card mapped to that...
by Boydie
Tue Oct 29, 2019 9:38 am
Forum: hardware
Topic: Opus Challenger 3 Drive not working
Replies: 12
Views: 445

Re: Opus Challenger 3 Drive not working

Have you excluded an issue with the 12V supply, given that everything that doesn’t use 12V (including Gotek) works?
I have a set of BBC-powered drives that are intermittently flaky, depending on how the power connector is plugged into the Beeb.
by Boydie
Sat Oct 26, 2019 8:00 am
Forum: off-topic
Topic: LOLPRICE
Replies: 2951
Views: 280405

Re: LOLPRICE

Anyone hankering after this gem for their collection? https://www.ebay.co.uk/itm/ACORN-BBC-Micro-Electron-ULTRA-RARE-Game-Weetabix-vs-Versus-The-Titchies/303318918234?hash=item469f37645a:g:GUoAAOSw6IVdocDd So rare they literally did give it away with cereal packets. Shame he’s not got an old Weetab...
by Boydie
Fri Oct 25, 2019 7:02 pm
Forum: acorn atom and system
Topic: Yarrb - redesigned
Replies: 55
Views: 1921

Re: Yarrb - redesigned

One for me too, please.

My other Atom will feel left out, otherwise. Besides, I’ve got a mountain of components going spare!
by Boydie
Wed Oct 23, 2019 6:44 pm
Forum: hardware
Topic: Very dead A3000 (now very much alive)
Replies: 20
Views: 834

Re: Very dead A3000

Pin 5 of IC10 is connected to Pin 18 of IC2. Pin 6 of IC10 and Pin 19 of IC2 are connected to LK15, which is not made (which is what my circuit diagram suggests should be the case). For reference, this is the signal on IC2 Pin 18: 6314D61A-25C0-4329-BAE8-187DFE3038B0.jpeg Edit: I’ve gone a bit furth...