P.R.E.S. AP5 - Original and Re-Design

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TheCorfiot
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Re: P.R.E.S. AP5 - Original and Re-Design

Post by TheCorfiot » Mon Sep 11, 2017 6:18 pm

Thank You Dave B, and Dave H for that matter

The AP5 works perfectly with the ELK103 ROM and My BBC IDE Interface, I'm in the process of compiling a nice HD Image :)

I'm going to beg DaveB or JGH to please modify the ADFSE00 ROM which I have attached to access the AP5 1MHz Bus I/O address.
It's very useful for use with the Model B in that you can Softload it to a SWR Bank using ADFS 133 and then hand over control so you can use the IDE HD with Page=&E00

Please, with sugar on top lol

Thx
Attachments
ADFS132eoo.txt
BIN File
(16 KiB) Downloaded 18 times

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hoglet
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Re: P.R.E.S. AP5 - Original and Re-Design

Post by hoglet » Mon Sep 11, 2017 6:29 pm

TheCorfiot wrote: I'm going to beg DaveB or JGH to please modify the ADFSE00 ROM which I have attached to access the AP5 1MHz Bus I/O address.
It's very useful for use with the Model B in that you can Softload it to a SWR Bank using ADFS 133 and then hand over control so you can use the IDE HD with Page=&E00
I'm not familiar with this particular ADFS version. But the IDE hardware is at the same address (&FC4x) in both the Elk/AP5 and the Beeb. So if it's not working in the Elk, then it's for some other reason.

Dave

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by TheCorfiot » Mon Sep 11, 2017 6:51 pm

oooh, Did not realise the IO address was the same... Must try it :)
The Floppy Access of course will be wrong :)

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by TheCorfiot » Mon Sep 11, 2017 6:54 pm

Electron wont even Boot (CTRL BREAK) Once it's been softloaded..

:(

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by hoglet » Mon Sep 11, 2017 7:05 pm

TheCorfiot wrote:Electron wont even Boot (CTRL BREAK) Once it's been softloaded..
Have you tried this version patched for the Elk by AlanD:
viewtopic.php?p=59497#p59497

Dave

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by TheCorfiot » Mon Sep 11, 2017 7:11 pm

Thank you my friend, I didn't even now that existed

Will try it later
Cheers
:)

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by TheCorfiot » Tue Sep 12, 2017 3:13 pm

Well ADFS135 Works on IDE fine but it's command set makes it pretty useless.
Also as Prime (Phill HS) found out with his Plus3 the Floppy Support doesn't work..

We have some great Hardware now chaps but sadly the Software support to use this Hardware at it's best is non existant, My Hardware skills are OK but sadly my software skills are non existent otherwise I would throw myself into developing a suitable E00ADFS ROM.

I Hope our resident Guru's JGH and Dave B can help

:)

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by davidb » Tue Sep 12, 2017 3:21 pm

I don't know much about filing system ROMs. :( I'm sure there must be existing ROMs for the BBC (Master Compact?) that could handle ADFS hard drives. Maybe someone has already made one of those work on an Electron...

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by danielj » Tue Sep 12, 2017 3:31 pm

The E00 elk ADFS had the SCSI code whipped out of it and needs two banks of RAM. I suspect the easiest thing would be to pull that apart and add the IDE code back in? (not that I'm volunteering at the moment!)

d.

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by TheCorfiot » Tue Sep 12, 2017 3:37 pm

danielj wrote:The E00 elk ADFS had the SCSI code whipped out of it and needs two banks of RAM. I suspect the easiest thing would be to pull that apart and add the IDE code back in? (not that I'm volunteering at the moment!)

d.
That I believe would certainly be the best way to go...

You Tease, You, lol... :)

I think we need to grab JGH before we lose him to the House of Commons lol :D

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by danielj » Tue Sep 12, 2017 3:41 pm

(I got tied up fixing ADFS 1.35 to work on the Master under OS1.2, and have never managed to get it to work with floppies :( )

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by CMcDougall » Tue Sep 12, 2017 5:03 pm

TheCorfiot wrote:Well ADFS135 Works on IDE fine but it's command set makes it pretty useless.
Also as Prime (Phill HS) found out with his Plus3 the Floppy Support doesn't work
A bit harsh Baz, you already knew the Plus3 was utter garbage, think DaveH has done an excellent job =D> on this RARE as hens teeth board (only 5 originals in universe? :? ), and works well with all my stuff with no problem at all. ((DataCentre, UPURS, MMFS, matchbox Co pro/s & eproms) not tried a old HD or Card on the IDE data centre....)
Have you tried DFS, it's the dogs bollox as you well know!! :lol: :wink:

PS if your elk 'hangs' as you said, press Shift T Break, then the CFS takes over , & burries ADFS :D
ImageImageImage

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by daveejhitchins » Tue Sep 12, 2017 6:03 pm

What's actually needed is the ACP ADFS E00 with the Hard Drive code put back in place, IDE code added, keeping Page at E00. So will need to use the Bank Switching, on the AP5, to gain the extra memory. The RAM overlay is there already . . . Oh! And JGH :roll: =D>

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by TheCorfiot » Tue Sep 12, 2017 11:52 pm

CMcDougall wrote:
TheCorfiot wrote:Well ADFS135 Works on IDE fine but it's command set makes it pretty useless.
Also as Prime (Phill HS) found out with his Plus3 the Floppy Support doesn't work
A bit harsh Baz, you already knew the Plus3 was utter garbage, think DaveH has done an excellent job =D> on this RARE as hens teeth board (only 5 originals in universe? :? ), and works well with all my stuff with no problem at all. ((DataCentre, UPURS, MMFS, matchbox Co pro/s & eproms) not tried a old HD or Card on the IDE data centre....)
Have you tried DFS, it's the dogs bollox as you well know!! :lol: :wink:

PS if your elk 'hangs' as you said, press Shift T Break, then the CFS takes over , & burries ADFS :D
LOL, it was not my intention to be Harsh in anyway, Dave H's Hardware is fantastic as always..
I do actually like both ADFS and DFS with no preference over the other but then I also like BBC Masters too.
I hope you don't stop talking to me now..lol

;)

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by aerworuld » Mon Oct 02, 2017 6:24 pm

Just wanted to say that this board is wonderful. I finally got around to soldering up a 9 pin connector to test the usb serial link on the (E)UPURS and everything is lovely. I sent a dsd floppy image to the laptop and one back to the Electron and all is good, I have tested the Beeb compatible user port with my AMX mouse and the hacked version of AMX Art that the genius that is Mr Barr did for me a few years back and that works fine too.

Big thumbs up for the AP5 redesign! =D> =D>

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by jms2 » Sun Jan 07, 2018 4:40 pm

I've got my board built up as well - no problems building it except the right-angled headers on the left and right hand sides were supplied as straight... I fixed this by just bending them over.

I have a 62256 (32k) SRAM to go in it, and I'm now at the point of burning a 64k rom (27C512). However, I'm a bit confused about how the RAM overlay works and the how differences between Modes 2 & 3 fit in with the available roms. I want to use it with MMFS, plus BeebSCSI.

I think my list of questions is as follows:

1) On page 12 of the manual the text at the bottom implies that the 62256 is the only supported SRAM type, but the table above states 16k RAM for Modes 2 & 3. Does this mean that these modes don't work with the 62256?

2) Would I be right in thinking that only a small part (up to 4k) of any SRAM is actually used (in the form of an overlay)?

3) Mode 2 has 3.5k overlay for MMFS, whereas Mode 3 has a 4k overlay for ADFS. But as far as I can see there is not yet a suitable version of ADFS which would make use of this, as the only versions of ADFS I can find are:

- ADFS 1.00, which has SCSI code but has page at &1D00 (and which has hardly any commands)
- ADFS 1.35, which is E00, patched by AlanD to include IDE code (but not SCSI), and which seems to have about the top 3.5k blank (not 4k)
- ADFS 3.31, also E00, but needs 32k SRAM to run from and has no HD code.

Presumably I'm restricted to the first of these for BeebSCSI, so is the 4k RAM overlay feature only provided to facilitate the writing of future ADFS versions?

Grateful for any guidance on this!

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by hoglet » Sun Jan 07, 2018 4:57 pm

I can have a stab at answering these questions...
jms2 wrote: 1) On page 12 of the manual the text at the bottom implies that the 62256 is the only supported SRAM type, but the table above states 16k RAM for Modes 2 & 3. Does this mean that these modes don't work with the 62256?
That's possibly a typo in the manual. These modes should work fine with a 62256. In fact, I'm not aware of any 16K static RAM devices.
jms2 wrote: 2) Would I be right in thinking that only a small part (up to 4k) of any SRAM is actually used (in the form of an overlay)?
Yes, that's exactly what it means.
jms2 wrote: 3) Mode 2 has 3.5k overlay for MMFS, whereas Mode 3 has a 4k overlay for ADFS. But as far as I can see there is not yet a suitable version of ADFS which would make use of this, as the only versions of ADFS I can find are:

- ADFS 1.00, which has SCSI code but has page at &1D00 (and which has hardly any commands)
- ADFS 1.35, which is E00, patched by AlanD to include IDE code (but not SCSI), and which seems to have about the top 3.5k blank (not 4k)
- ADFS 3.31, also E00, but needs 32k SRAM to run from and has no HD code.

Presumably I'm restricted to the first of these for BeebSCSI, so is the 4k RAM overlay feature only provided to facilitate the writing of future ADFS versions?
Yes, this is to allow a future version of ADFS to be written.

I'm not 100% sure what Alan D's 1.35 was created from. So it's possible there was a SCSI version of this. I'll do some digging....

I'm currently using my own build of "ADFS 1.00", which is actually ADFS 1.30 disassembled and back-ported to the Electron hardware addresses. This is different to the original ADFS 1.00, as many of the serious 1.00 bugs have been fixed. I'm not sure floppy support works though. It's available here:
https://github.com/hoglet67/ADFS130/releases

Dave

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by hoglet » Sun Jan 07, 2018 5:20 pm

Someone really should draw a family tree for all ADFS versions!

There was another branch that might be of interest: ADFS 1.31 (SCSI) and ADFS 1.32 (IDE patched my Michael).

The image for ADFS 1.31 is here (amongst other places):
http://archive.retro-kit.co.uk/BBC.nvg. ... index.html

And some useful commentary here:
http://lists.cloud9.co.uk/pipermail/bbc ... 03449.html

So it seems this is:
- Model B specific
- Contains Floppy and SCSI HD Drivers
- Uses a 4K RAM overlay to give PAGE=&E00
- Of unknown origin (possibly Solidisk rather than Acorn)

But it looses the *COPY command, which seems a major issue.

Dave

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by jms2 » Sun Jan 07, 2018 5:52 pm

That's very helpful, thanks Dave.

On reflection I see that you basically have to have one, and only one, FS working with PAGE at E00. This is because the two overlays are different sizes. Ideally this would be ADFS, because DFS @1900 is pretty standard and not too inconvenient, whereas ADFS @1D00 is a bit of an imposition.

So if I went with ADFS my rom would look like this:

Mode 3
0000-2FFF Spare and not really usable as there isn't anything else which uses a 4k overlay.
4000-6FFF ADFS 1.31 (needs patching with Elk hardware addresses)
8000-BFFF Spare - could use for any 16k ROM though
C000-FFFF EMMFS @1900

... or could do the equivalent in Mode 2 and use ADFS 1.00 in C000-FFFF.

Is that right?

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by hoglet » Sun Jan 07, 2018 6:20 pm

jms2 wrote: So if I went with ADFS my rom would look like this:

Mode 3
0000-2FFF Spare and not really usable as there isn't anything else which uses a 4k overlay.
4000-6FFF ADFS 1.31 (needs patching with Elk hardware addresses)
8000-BFFF Spare - could use for any 16k ROM though
C000-FFFF EMMFS @1900
Yes, that looks right to me.

But you might be the first to actually test this!

Also, porting ADFS 1.31 to the Elk may be more involved that changing the I/O addresses. The Beeb and Elk floppy drivers are quite different, as the Elk uses polling rather than NMI.
jms2 wrote: ... or could do the equivalent in Mode 2 and use ADFS 1.00 in C000-FFFF.

Is that right?
Yes, you should be able to use ESWMMFS at 4000-75FF (with a 3.5K RAM overlay), and ADFS 1.00 in C000-FFFF.

All those builds exist today, so you could try that immediately.

Oh, and the spare regions would need special software to use. The AP5 include an additional bank switching mechanism to allow 32K of ROM to fit into a 16K slot, but again nothing that uses that exists today.

Dave

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by jms2 » Sun Jan 07, 2018 6:55 pm

Great, as you say I'll try the Mode 2 solution first because it's a lot easier.

Regarding bank switching, I had assumed this would be something done manually by the user making the pokes described in the manual. It can't be done from within a sideways rom, presumably, as to do so would pull out the rug from under the feet of the currently executing rom.

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by hoglet » Sun Jan 07, 2018 8:32 pm

jms2 wrote: Regarding bank switching, I had assumed this would be something done manually by the user making the pokes described in the manual. It can't be done from within a sideways rom, presumably, as to do so would pull out the rug from under the feet of the currently executing rom.
I think the idea is you could (in principle) write ROM that needs 32K of code, organised as two 16K "banks". Each bank would contain an identical subroutine to perform bank switching, so when the bank switching actually occurred, there wouldn't be a crash. It's a bit trickier than this in practice, but you get the idea...

Dave

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by daveejhitchins » Mon Jan 08, 2018 8:48 am

hoglet wrote:
jms2 wrote: 1) On page 12 of the manual the text at the bottom implies that the 62256 is the only supported SRAM type, but the table above states 16k RAM for Modes 2 & 3. Does this mean that these modes don't work with the 62256?
That's possibly a typo in the manual. These modes should work fine with a 62256. In fact, I'm not aware of any 16K static RAM devices.
Sorry about that . . . The device should be listed as a 32K RAM, I'll correct this.

Dave H :D
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Re: P.R.E.S. AP5 - Original and Re-Design

Post by jms2 » Mon Jan 08, 2018 12:40 pm

While you're in correcting mode Dave, I noticed several other trivial errors/typos in the manual which you might want to include at the same time. I can't remember what any of them are right now, but later on when I get home I could send you a list.

All of them were insignificant apart from the 16k/32k mixup.

One thing which I think I remember is that neither the manual nor the markings on the PCB state which way round the card should be when inserted into the Plus 1. This probably doesn't matter though, as I guess it'll only fit in one way round due to its shape. I've not actually tried yet! With a BeebSCSI hanging off one side it looks like everything will fit fine.

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by daveejhitchins » Mon Jan 08, 2018 3:47 pm

jms2 wrote:While you're in correcting mode Dave, I noticed several other trivial errors/typos in the manual which you might want to include at the same time. I can't remember what any of them are right now, but later on when I get home I could send you a list.
Yes please . . . If you're not careful you'll end up as my proof reader :wink:
jms2 wrote:All of them were insignificant apart from the 16k/32k mixup.
I'm not too worried about this one, as Dave (Hoglet) says, you can't obtain a 16K RAM - You watch, someone is bound to prove me wrong :mrgreen:
jms2 wrote:One thing which I think I remember is that neither the manual nor the markings on the PCB state which way round the card should be when inserted into the Plus 1. This probably doesn't matter though, as I guess it'll only fit in one way round due to its shape. I've not actually tried yet! With a BeebSCSI hanging off one side it looks like everything will fit fine.
I always do label the boards IF they can be fitted the wrong way round. But as you've pointed out you can't, due to the shape (well you could if you take the lid and tray off the Plus 1 :shock: ).

Dave H :D
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Re: P.R.E.S. AP5 - Original and Re-Design

Post by jms2 » Mon Jan 08, 2018 10:48 pm

Sorry Dave, it's a bit late now to write that list today. Hopefully I'll get time tomorrow. I have been using what little spare time I did have productively though... getting my AP5 running for the first time!

Everything I tried works! =D> Well, except for MMFS, and I know why that was - after all the discussion about ram overlays and modes, I forgot to put any jumpers in... :oops: correction, I had both j1 and j2 fitted, this mode 3 not mode 2.

BeebSCSI seems to work fine with ADFS 1.00. Its the first time I've tested the board out on any machine. Thanks to diminish and Jason Flynn for their work on this excellent project.

PiTubeDirect Cobra works too, with one exception: *fx 151 230 n seems to do nothing at all. Anyone know why?
Last edited by jms2 on Tue Jan 09, 2018 8:01 am, edited 1 time in total.

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by jms2 » Tue Jan 09, 2018 8:00 am

That's odd... I've now got j1 and j2 set up correctly for MMFS, but I still get a Card? Error with an MMC board connected to SK3. This board and card work fine with a BBC, but I'm not certain I've tested them with MMFS, only with the old DFS0.9 MMC system. Does this mean I need to do something different to the card?

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by hoglet » Tue Jan 09, 2018 8:23 am

jms2 wrote: PiTubeDirect Cobra works too, with one exception: *fx 151 230 n seems to do nothing at all. Anyone know why?
On the ELK the address of the tube is different. So you need to do *FX 147 230 n

Also, do update to the DiamondBack release. It fixes a serious bug in the GPU code, and also adds an Elk mode that patches the Z80 tube client ROM for operation on the Elk. This allows CP/M to work properly. You need to set elk_mode=1 in params.txt

Dave

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by hoglet » Tue Jan 09, 2018 8:25 am

jms2 wrote:That's odd... I've now got j1 and j2 set up correctly for MMFS, but I still get a Card? Error with an MMC board connected to SK3. This board and card work fine with a BBC, but I'm not certain I've tested them with MMFS, only with the old DFS0.9 MMC system. Does this mean I need to do something different to the card?
Which MMFS version and ROM file are you using? I'll try and replicate.

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Re: P.R.E.S. AP5 - Original and Re-Design

Post by hoglet » Tue Jan 09, 2018 11:17 am

hoglet wrote: Which MMFS version and ROM file are you using? I'll try and replicate.
I've just built myself a similar ROM image:
0x0000 = Blank
0x4000 = U/ESWMMFS.rom from here
0x8000 = Blank
0xC000 = ELK100.rom here

Here's the 64K ROM image:
elk_eswmmfs_adfs.zip
(21.57 KiB) Downloaded 13 times
I've put the AP5 into Mode 2 (J1 missing, J2 present).

ADFS detects BeebSCSI, and you get PAGE=&1D00.

MMFS detects a MMC Interface plugged into SK3 (the right hand User Port socket, when viewed from the front), and you get PAGE=&E00 (with ADFS unplugged).

The ROM ordering is such that ADFS takes precedence.

Dave

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