exxos's Atari, Amiga & retro forum

Hello,

Looking to see if anyone is using the original SMD-340 on the H5 board?

I am having odd problems and it would seem the board was never designed to use the original Atari drive, so I am trying to see how others may have used it, maybe had issues? might not be drive related.

I want to be able to use the 1.44 with the 1.44 gal and be able to access everything from 360k to 1.44mb floppies/

James

Hi @Bikerbob could you please explain these issues you are experiencing?

You can use any drive on the H5. Your actual problem is modding the drive to work with 720k / 1.44 automatically. I've only modded the MPF920.

You'll need to mod your drive like the MFP920 to provide a signal when an HD disk is installed, pretty sure there is a write up, but I can't find it right now.

I know with the H4 there were jumpers to set to enable the functionality to allow 1.44MB and lower disks with it, so I'm assuming you need to do similar with the H5.

The jumper settings are found in the H4 section, @exxos is it still necessary to set these jumpers on the H5?

rubber_jonnie wrote: 22 Sep 2021 16:56 The jumper settings are found in the H4 section, @exxos is it still necessary to set these jumpers on the H5?

The jumpers are there to force 1.44 or 720k mode when the HD select wire is missing. The drive basically sets the jumpers for you..

The MPF920 mods are here https://www.exxosforum.co.uk/atari/last/floppy/index.htm.

To use a EPSON SMD 340 or 300 drive you must at a wire for the DD/HD Select signal like at the SONY drive ...

frank.lukas wrote: 22 Sep 2021 18:23 To use a EPSON SMD 340 or 300 drive you must at a wire for the DD/HD Select signal like at the SONY drive ...

This would not actually work because pin 2 not connected to anything on the motherboard. If pin 2 is generally not used by *any* drives, then this could be a modification on future motherboards. Where like in your image, the select wire could be done internally on the drive and passed by the ribbon cable connector instead of a separate wire.

okay I stand corrected, it seems I did this modification at some point and totally forgot all about it :roll:

A quick look back through the H5 revisions, this "feature" has always been there.


So it would be interesting if someone can try this out with a MPF920. Routing the "fly lead" internally to pin two on the floppy connector..And of course leaving JP18 open.

Just for completeness I found the MPF920 DS.

OK, so I am getting that I can either run it to the one pin on the Jp 18 or to the pin 2 on the controller correct??


James

Bikerbob wrote: 22 Sep 2021 20:44 OK I read your thread on the 920 mods Exxos, but I only see where you are using your HD mod board. Where do I attached the HD detect wire (white wire in your image) to the H5 c1 board?

It is explained in the jumpers page, it is also explained on the motherboard, and it is even shown in the image I posted above just.