kodak80 H4 build (x2)

[exxos]

I would assume emutos would work in tos206 space. But there is nothing on the H4 to decode that address range.

[PhilC]

I would assume emutos would work in tos206 space. But there is nothing on the H4 to decode that address range.

Only the 192k version would work on my Mega within address decoding. And yes your right exxos, the 256k does work in the 206 address space

[exxos]

You need one of these. https://www.exxosforum.co.uk/forum/viewt ... 590#p33519

[PaulJ]

I think exxos means that it needs external decode logic adding to address the 256k space from 0xE0000000...that's in the STE and some boosters but not natively in the original ST MMU etc.

Well Ya got me there.. but I never use the H4 rom only the rom on Exxos's IDE or flashy clock board which support the $e00000 - $0000 decode addition. I'm not much of a gamer so I rarely use anything that resides @ $fc0000. So in essence @kodak80 if you have an Exxos IDE, flashy clock, or a Lightning card you should be able to use 256k TOS.

[kodak80]

So one of these would also do the trick: https://www.exxosforum.co.uk/forum/viewt ... 450#p33287

[PaulJ]

So one of these would also do the trick: https://www.exxosforum.co.uk/forum/viewt ... 450#p33287

Have 3 on the way to assemble and test :D

Yup.. those will decode $e00000, $fc0000, and $0000 which is exactly what you need. :)

[kodak80]

I should correct this as my typing missed the words “I will” from above and so I will have 3 on the way as I plan on ordering some once they are available although the update on the other thread may mean I will be waiting a while.

[JezC]

Just soldered the pins into one to see how it sits on the H4 board (board 3):

@kodak80 I'm trying to finalise another Farnell order for some bits to build up the bodge boards for my H4s as well as various bits for the IDE boards...

I was wondering which header pins you used when you built up your H4 bodge boards?

I've got to remove the 245 that is currently soldered into the first H4 board & will probably then fit a socket, then plug the completed bodge board into that socket. I think I have turned pin sockets to hand, but I can get some more conventional sprung sockets to use on the motherboard instead & then I might be able to use the normal header pins (as used for much of the H4 build)?

So, because I've probably made the above very confusing :lol: :roll: ), my plan is:-
1/ remove the existing 245 from the H4 board
2/ fit a sprung contact socket to the main H4 board in this location
3/ use standard square cross-section header pins to solder into the bodge board
4/ fit the inverter & 245 into the bodge board

Then I can check it boots & runs OK from floppy/Gotek & then try it with an external ACSI hard drive.

I've been in two minds whether to do this mod to the H4 boards up to this point, partly because I still have to fit the cartridge port & MIDI sockets (the latter are part of this next order :roll: ) as well as the ACSI port connector itself but also because at least one H4 will be home to a TF536 board...and from several comments it seems that the ACSI port is not likely to work well alongside the TF536 (or at least not until TF sprinkles his usual magic dust on it all, and I'm sure I've read that he isn't planning that for a few years...if ever)

If anybody else reading this has managed to get any ACSI devices (or even SCSI devices via an ACSI adaptor) working with the TF536 then I'd be delighted to hear the details! :D

[kodak80]

Just soldered the pins into one to see how it sits on the H4 board (board 3):

@kodak80 I'm trying to finalise another Farnell order for some bits to build up the bodge boards for my H4s as well as various bits for the IDE boards...

I was wondering which header pins you used when you built up your H4 bodge boards?

I used standard strip of turned header pins.

[JezC]

I used standard strip of turned header pins.

Ah, OK - I'll tr and find them on Farnell (if I can find _any_ headers on there without a £15 delivery surcharge :x )...failing that I guess i'll order from Rapid or similar instead...

Thanks for the info!