Hello, Yes, the board has a blitter. I'll swap that one as well to see. And I've replaced the Tos, MMU, Glue, Shifter, DMA. All those are on a socket. One thing that's strange, in diagnostics doing the OS-Check. It may work one time, and give an error the next time. Either CRC-check or 4 addresses b...

Hello, Today I've found a strange puzzle. A MegaST 4 board will not boot, no display and no floppy activity. Looks like an impropper reset. So I conected a diagnostics cartridge. Display, Ram, Timing, Blitter and also Floppy work just fine. All tests ok. Yet the board will not boot without the diagn...

This is a picture of a MegaST-board.
It has a small PCB with 2 pieces Gal16V8 on them and wires all over the board.
My guess is, it's a screen blaster.
But I'd like to be sure and also need the software for it.
Any comment and help is welcome.

BR/
Guus

Hello,
Maybe not the best place, so move if needed.
Today I've found a version of Tos 1.04 that I didn't know about.
It's a Dutch version. BR/
Guus

P.S.
The Rom's were taken from a working MegaST board that was in one of my MegaST's.\
So I took my Eprom programmer and read the chips.

Hello, Once uppon a time, I saw some notes on how to get rid of the startup delay in Tos 2.06. I mean the delay that's needed for a HD to spinn up. As I'm using Ultrasatan or a CF-card as a drive replacement, this delay is not needed and it annoys me. And now, I'd like to find this again. But it kee...

Hello Exxos, A selector switch is exactly what I wouldn't recommend. Yes, it's convenient. But also very easilly put in the wrong position. And that may be hard to prove. Why not have a couple of holes in the PCB. Depending on how the wires are soldered in those holes, it is a voltage setting. And h...

Hello Exxos, Congrats on this new product. Regarding the voltage selection, I have a suggestion. I would make it such that it needs soldering to set the correct voltage. That way, it's not possible to select a wrong voltage by accident. And I guess this will effectively prevent claims and incidents....

Hello, Today I've spent some time with the floppy drives again. My subjects were 2 Teac FT235 drives, 1,44Mb capable on a PC. After changing the device ID to 0, they worked in 720k mode. After some checking, I found that connecting S7 does the trick, I get an output on pin 2. To make the HD module s...

Great job, thanks for this ! As the shifter often is quite picy regarding timing, it is also a party stopper for some speedups in the system. Maybe with this "shifter replacement" it is also possible to get the Ram and Rom to work at double speed? The MMU generaly can handle higher speeds....

Hello Exxos, About the disk drives, I have 4 pieces SMD380, 2 have a switch and 3 don't. And I also have an SMD 300 (From a Falcon) that has a switch. So far I've checked the ones with the switch. They all have the controller : SF9200-K on them. The PCB on the SMD300 is different from the other 2 I'...