Vectorlight's A3010 IDE mod : step by step guide

[Zarchos]

1st step : get a naked board :

[vectorlight]

Here's a list of the things you'll need to get Zarchos , prefixed with the identifier which matches with where they need to go on the board you have. The links are for items on Ebay UK, I didn't look for the best value components so have a look for the same items from a local supplier:

ICs:
IC1-IC2 = RISC OS 3 ROM's (You will already have these!)

IC3 = HC573 - http://www.ebay.co.uk/itm/74HC573-CMOS- ... 1690760883

IC4 = HCT573 - http://www.ebay.co.uk/itm/74HCT573-Octa ... 0552681706

IC5 = HCT14 - http://www.ebay.co.uk/itm/74HCT-CMOS-74 ... 1226775297

SMD 0805 Components:
R1-R8 = 68 ohm Resistor - http://www.ebay.co.uk/itm/SMD-SMT-0603- ... 2092882745
R9-R11 = 33 ohm Resistor
R12, R17 = 22 ohm Resistor
R13-R14 = 10K ohm Resistor
R15 = 4K7 ohm Resistor
R16 = 220 ohm Resistor (Only fit if you want to overclock the CPU)

C1, C2, C5 = 100nF Ceramic Capacitor - http://www.ebay.co.uk/itm/50x-SMD-0805- ... 0973425038
C3 = 100nF Ceramic Capacitor (Only fit if you want to overclock the CPU)

Other Components:
C4 = 100uF Electrolytic Capacitor - http://www.ebay.co.uk/itm/Range-of-Radi ... 1191368791
C6 = 47uF Electrolytic Capacitor

X1 = IDE 44-pin Header - http://www.ebay.co.uk/itm/190533192334

Header Sockets for IC1-IC2 ROM Sockets (The ROM's will sit in these!) = Round Header Sockets (You will need enough for 4 rows x 21 pins) - http://www.ebay.co.uk/itm/381576373379

Board Mounting Pins (These when fitted will allow the board to be plugged into the existing ROM sockets) = Round Header Pins (You will need enough for 4 rows x 21 pins) - http://www.ebay.co.uk/itm/401031627149

X2 = DIP 14 Socket (Only fit if you want to overclock the CPU. Remove pins 2,3,5,6,9,10,12,13) - http://www.ebay.co.uk/itm/10-x-14-Pin-D ... 1769195693

[vectorlight]

Hi Zarchos,

I've taken some pictures to help with the assembly of the board and have written it up here:

http://www.vectorlight.net/retro/comput ... dification

Let me know if you need any more info.

[Zarchos]

Great !
Thank you.

I'll try all this after my bits of coding are completed. I'm not far from the results I wanted to achieve, now.

[Trapper]

Assume you need an ARM250 to do this?

[vectorlight]

Assume you need an ARM250 to do this?

That's right. I did have a quick look at the adelaide schematics and if I recall 1 or the required signals was not tracked out of IOEB making this mod pretty much impossible

[steve3000]

Assume you need an ARM250 to do this?

That's right. I did have a quick look at the adelaide schematics and if I recall 1 or the required signals was not tracked out of IOEB making this mod pretty much impossible

That's interesting, which signal? There are references (in the TRM as i recall) to the Adelaide board design for the A3020 and A4000, which presumably would require all signals for the IDE interface...but I've never heard of such an Adelaide A3020 or A4000 computer actually existing.

Maybe there was something fundamental such as this which excluded any release of an Adelaide A3020 or A4000?

[vectorlight]

I recall looking at it in Jan or Feb, not sure off the top of my head which one it was, maybe I was wrong I'm not around at the moment but will double check when I get back

[danielj]

Just with a cursory glance at the schematics, I'm struggling to find anything missing

d.

[vectorlight]

Just with a cursory glance at the schematics, I'm struggling to find anything missing

d.

Perhaps I'm wrong If anyone wants to give this a try on an adelaide machine let me know

[danielj]

And we're off... Typically I'm having to wait an extra day for the 4k7 resistors to turn up *shakes fist at sky*

d.

[vectorlight]

And we're off...

Awesome, you got it and have started already

[danielj]

Yup Thank you! - hopefully will finish it off over the next couple of days. BTW, where did you take the +5V/GND from?

d.

[vectorlight]

BTW, where did you take the +5V/GND from?

d.

Cool! I took the +5V/GND from the test tabs on the left, the same as munchausen did, here is a pic of the board from his thread:

[Andy1979]

This is great work Vectorlight - suspect it would have been quite a big seller back in the day.

Afraid I am not brave enough to try it on my Adelaide A3010 as I already have a working IDE podule. Looks from that photo like Munchausen has the same Simtec 2mb -> 4mb upgrade that I do.

Wonder if something like this would work in the Bush IBX100 internet box?

[vectorlight]

Afraid I am not brave enough to try it on my Adelaide A3010 as I already have a working IDE podule.

Yeah I can understand, it's a fairly involved mod. That said, when I get my adelaide working again I will have a go

[Zarchos]

@Andy1979 : I've got one of these memory upgrades, and in fact it's a 3 Mbytes RAM upgrade (it's even written on it).
It means if you wanted to install some 50 ns RAM chips, you'd have also to replace the onboard 1 Mbyte. (if you're interested by the other fast A3010 project).
It's OT in this thread but worth noting : it's not a 'true' 4 Mbytes RAM upgrade.
There are no 2 to 4 Mbytes RAM upgrades ... there is either this 3 Mbytes upgrade, to 4, or 4 Mbytes and the onboard 1 Mbyte isn't used.

If some real experts (not me) have different opinions, please tell us.

[Andy1979]

@Andy1979 : I've got one of these memory upgrades, and in fact it's a 3 Mbytes RAM upgrade (it's even written on it).
It means if you wanted to install some 50 ns RAM chips, you'd have also to replace the onboard 1 Mbyte. (if you're interested by the other fast A3010 project).
It's OT in this thread but worth noting : it's not a 'true' 4 Mbytes RAM upgrade.
There are no 2 to 4 Mbytes RAM upgrades ... there is either this 3 Mbytes upgrade, to 4, or 4 Mbytes and the onboard 1 Mbyte isn't used.

If some real experts (not me) have different opinions, please tell us.

@Zarchos - you are correct that the board has 3mb on it now, but my A3010 came with the upgrade to 2mb, with a 512K ram chip in each of the expansion sockets. A few years later Simtec sold me this kit which had 2mb on the PCB and I had to remove the existing 1mb upgrade and reinsert it into the Simtec board to give 3mb plus the onboard RAM. This made it a cheaper way to upgrade to 4mb if you already had 2mb installed. Think it was £89 at the time, whereas the IFEL kits were over £100. Sorry, OT as you say.

[danielj]

Tell you what, this is slightly intense...

[danielj]

Right... I'm trying this on an issue 2. Pin 27 of the SuperIO (Iocs16) seems to be wired to Pin 22 (Ided7)... I'm guessing this just makes the disc controller give up doing anything ide-y?

Now, I'm not sure why, but my spidey sense suggests that wherever the track from pin 22 is leading, it should be cut?

(c.f. http://www.chiark.greenend.org.uk/~theo ... 82c711.pdf and attached PDFs...)

[vectorlight]

Tell you what, this is slightly intense...

Yeah probably the hardest part that bit, looks like you've done it though .

Now, I'm not sure why, but my spidey sense suggests that wherever the track from pin 22 is leading, it should be cut?

Wierd, I haven't noticed them wired together. I'm away for a week so cannot look at mine. Both looked to me to be not tracked at all. In the end I didn't bother with IOCS, though in the other thread theres talk of grounding it to be safe. Have you another A3010 (iss 1) to compare?

[danielj]

No, I've got no other A3010s, just this one. I can see both of them clearly tracked on mine though, and they buzz together. The track *seems* to go somewhere too. I'm guessing it's pulling up or down - I can't see any other use for it. Ensuring Ided7 isn't connected to anything other than the IDE port would seem to be a good idea though. It'd be good to see a schematic of the issue 2

Apart from that I'm getting a blank screen on start up - popping it out and putting the ROMs straight back in it's OK, so something must be holding the processor up. I'll buzz out the board and report back

d.

[danielj]

Further - they're both wired to R56, not listed in the TRM, which seems to be a pull up. If Iocs16 is pulled up, my reading of the datasheet is that the controller will never be ready for a data transfer?

I think removing R56 and cutting the Ided7 track would seem to be the best idea. And possibly grounding Iocs16? Although it is wired up on the A3020 interface via a pull up...

d.

[danielj]

So, snippy a track and remove (or put to one side) resistor:

And we're off!

Brilliant work vectorlight! Kudos


d.

[vectorlight]

Awesome, well done! I was beginning to think that the ISS 2 board was going to be a real problem, but looks like you've figured it out Why there's a difference on the ISS 2 board I have no idea

Have you tried different lengths of IDE cable as one issue I had with mine but could never figure out was that my CF cards would not work with short (5CM) cables but did work perfectly with long (20CM) cables.

The next question is how best to mount the drive

[danielj]

So far I've just tried a real one with a short cable (5cm) and that's fine. I haven't got any CF adaptors to hand yet, but should have some for testing this week.

d.

[Ste]

Hi, I'd like to give this project a go. Where could I buy the initial board from? Thanks.

[Ste]

So, I've now got the bare board from Vectorlite!

I figured I'd document my progress on here, just as soon as the rest of the parts arrive. Have to admit, this is a little more complicated than I'm used to, but even if I fail I'll still be the envy of the neighbourhood with the most expensive doorstop in town! Yay.

[danielj]

Weee! Good luck!
Nice and slow, and plenty of flux! And get a magnifier headset if you don't have one - most useful thing!

d.

[Ste]

I...don't have one. But I'll look it up! Cheers.