exxos's Atari, Amiga & retro forum

DoG wrote: 14 Apr 2021 18:40

Cosmic Puppet wrote: 14 Apr 2021 18:00Is that a device which can be plugged in between the UltraSatan and Hard Disk port?

You remove the DMA chip (usually in a socket) and put a small PCB in the socket and then the DMA chip back on the PCB. A small little sandwich.

That sounds great. I didn't even know about this.

Oh, it's not designed to fit inside an 520 STFM.

This probably a rabbit hole I'm going to have to leave. :lol:

@exxos I'm pretty sure Cosmics WD chip is socketed, ill check.

Hmm checked the photos and although I fitted the bus resistor it isn't socketed. I'd be happy to socket & replace @Cosmic Puppet 's chip with a VL varient IC if he would like. Just message me Tone.

Steve wrote: 14 Apr 2021 19:23 @exxos I'm pretty sure Cosmics WD chip is socketed, ill check.

It's not in his earlier photo that shows the RP attached to the data lines.

rubber_jonnie wrote: 14 Apr 2021 19:34

Steve wrote: 14 Apr 2021 19:23 @exxos I'm pretty sure Cosmics WD chip is socketed, ill check.

It's not in his earlier photo that shows the RP attached to the data lines.

Isn't it the DMA that need changing?

DoG wrote: 14 Apr 2021 18:40

Cosmic Puppet wrote: 14 Apr 2021 18:00Is that a device which can be plugged in between the UltraSatan and Hard Disk port?

You remove the DMA chip (usually in a socket) and put a small PCB in the socket and then the DMA chip back on the PCB. A small little sandwich.

Thanks. I'll keep my eyes open for a future 520STFM version, as I'd be able to try that myself.

So this morning I tried out formatting a floppy disk on TOS 1.04 with the UltraSatan powered but with no SD cards and it worked perfectly. No corruption. Was able to read it fine whilst in EmuTOS.prg and was able to swap it between PC and Atari via my MPF82E.

Having the UltraSatan unplugged garners the same results. It's only if the UltraSatan is plugged in and switched off that these odd issues arise with corruption.

Just wanted to post this now that I've clarified the conditions.

I guess it depends what buffers they used on ultrasatan .. I mean if its a IC which is powered down the it could be shorting the DMA bus out. Open it up, see what's there ;)

exxos wrote: 17 Apr 2021 14:17 I guess it depends what buffers they used on ultrasatan .. I mean if its a IC which is powered down the it could be shorting the DMA bus out. Open it up, see what's there ;)

I daren't. I guess the fact that it works when switched on is preferable. :lol:

I've taken a couple of picture of the Lotharek version of the UltraSATAN.

It looks like the bus interface is done using MOSFETs.

Excuse the distortion, I was using my iPhone in x2 magnification mode through a desktop magnifier to try to get enough magnification.