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You're right - the Acorn Speech system isn't compatible with a Master. I think I'm right in saying that the communication protocol it used was repurposed to provide the CMOS ram-based configuration memory.

That's really interesting, I didn't know the LED did any of those things!

I got a couple of fairly big chunks of wood and cut a wide slot into them. The board slides into the slot, and the wood pieces become "feet" for it. The only problem is that I can't always find the pieces of wood when I need them...

This looks like a brilliant initiative Jon! I was going to mention ZIDEFS but Ian beat me to it. The other one that I have is the Armstrong-Walker IDEFS (running on an HCCS podule). The documentation is available, but doesn't say anything about SWIs. Is there some code I can run to get it to tell me...

You're doing OK! I remember reading the bit in the Electron User Guide about assembly language, and not comprehending it at all. I had to come back to it about three times before I eventually figured it out. As a beginner, writing your own assembly language routines from scratch is really hard, beca...

That's a good point - I had forgotten about SCSI2SD and I agree it would be an equally good solution. However I have decided to go down the IDE route with one of Ian's boards. Keeping the SCSI board would make more sense if I had other SCSI devices, but I don't! If anyone is looking for a SCSI podul...

Thanks Ian, to be honest I was just working through a sort of self-discipline process in an attempt to resist any accusations of compulsive buying of interesting retro hardware! 8-[ My colleague told me that he has amassed quite a few "NOS" SCSI drives, so adding one of those could have be...

Hello Ian, I have an A420/1 which has an old SCSI card and drive. This all still works, but the drive is small and won't last forever. I have a possible option to obtain a new SCSI drive, but would you say that putting in one of your podules would be technically a better option? I'm not conversant w...

My reading of the purpose of the mod was that it specifically addressed compatibility issues with 610/710 cards, so it might not be necessary with a StrongArm. But in all probability your card is probably already modified. The easy way to tell is to look at the capacitor next to the 486 (C20). If it...

Good news - I have completed the modifications described in App Note 297, and now the PC card works! So for future reference, if anyone has a Mark 2 PC card with a 486DX4-100 processor, and problems in a RiscPC600, check that this mod has been done. There seems to have been a recall at the time so p...

When I took mine apart, I found everything looked good except that some of the conductive pads had some "dust" on them. It looked slightly metallic but that might have just been an illusion - more likely it was something non-conductive. Anyway, I just brushed it off. No solvents were needed.

I did fix it. As Ian says, I think it was the rom sockets.

Hello and welcome!

The N/S/E/W compass is simply to make it easier to reference the position of components on the main board. So you can say “R99 is west of C18” for example.

Crikey. I check out the "current" Risc OS world every year or so just to see what's going on, so I hadn't seen this.

I'll pop back in another 12 months then...

This looks really excellent - well done!

I have a Slogger Turbo board but have not got around to fitting it because of the surgery needed versus the speed gain achievable. I could be tempted with your version though...

Unfortunately, I don't think there is.

I am not an expert with !MakeModes, but I would think the best option would be to define a mode which is vertically smaller, such that it fits on the screen. However I'm sure you have already tried that.

Cheers - I'll give those a try. Based on the photos alone, I wouldn't have realised they were precise enough.

I hadn't thought of doing it that way. In the past I have used a knife to cut the legs but that's not the right way to do it (too risky). If it's possible to buy snippers which are fine enough, I'd definitely be happy to try it.

IanJeffray wrote: ↑

Mon Dec 28, 2020 6:40 pm

For the cost of a 244, just swap it.

You haven't accounted for my SMD soldering skills!

Actually I'm not too bad, but I don't have a hot air thing for removing ICs. I can solder them down OK, just not get them off. I might be able to borrow one though, so I'm working towards that.

That's interesting - I get something a little bit like that near the mouse pointer, but only occasionally.

Jon, when you say resoldering, do you mean specifically around IC33 or elsewhere?

Looks very good, and super smooth as always! =D> I must admit I know nothing about New Rally-X (or the original version for that matter), so having downloaded this out of curiosity I had to do some research to see how this differs from the arcade version. The zoomed-out version seems fine to me, I g...

I have had a good look for any other RiscPC CPU cards, and it seems that I don't have them. However, in the process I did manage to find the paper manual for PCPro3, and also for my Mozart card. I have been doing some reading of comp.sys.acorn.extra-cpu and it seems that the problem I am seeing is n...

That's really cool! Building it is somewhat beyond my ability though, hopefully a Windows binary will become available for download.

Well, I removed C32. This didn't have the transformational effect that I was hoping for, but it did help in a way... the PC card now fails in a far more predictable manner. ](*,) As it boots, the key steps are: - ROM checksum failure (the address at which this happens varies) - Main ram OK - There i...

This thread suggests that the PC card is very sensitive to the timings of the overall system, and in particular the status of C32 on the main board: https://stardot.org.uk/forums/viewtopic.php?t=17373 I wonder if recapping the main board is where I need to go next... EDIT: Having read up on it, I se...

Interestingly, these cards seem to be quite readily available on Ebay at the moment. I don't really want to spend £70 on one, but looking at the photos I see that C20 is typically not the same as the one on my board. This one is a totally different shape, and is 33uF if I'm reading it right. DX4 car...

OK thanks! I guess this means the fault must lie somewhere else then. For what its worth, I found that my multimeter has a capacitance testing function and I measured the values as follows: New 10uF -> 11uF measured Old 10uF 16V -> 8uF measured (this was the leaky one) Old 10uF 16V -> 14uF measured ...

Well, I have managed to replace all three electrolytic capacitors on the 486 card. It still doesn't work, but I feel like I may have discovered something... First I changed the obviously leaky one, marked 5N 10 16V. I thought that this was a 10uF, 16V item and so that's what I replaced it with. This...

Excellent, thanks Mark!

Hopefully I'll get some quiet time to think about this over Christmas. I think it will be all about making several amendments to the parasite code to work around the Elk internal numbers. Nothing major I think, I just needed to recalibrate my expectations of what's involved.

Lurkio and EdwardianDuck beat me to it!

I thought that maybe the use of STRING$ was a problem too, because you have defined a string name which is the same as that of a BASIC keyword. However it didn't seem to cause a problem in this case.