exxos's Atari, Amiga & retro forum

Adapter pcb to plug into most STFM C070789 machines.

It is possible to fit the board into the ROM sockets, but the extra height may not allow the metal shield to fit correctly.

New design allows switching from UK TOS102 to UK TOS104 via jumper link on PCB. ROM is a fast PLCC type compatible (and required) for V1.5 booster .

This kit should also fit motherboards with a single row of ROM sockets under the PSU.

HOME PAGE
http://www.exxosforum.co.uk/atari/last/tos/index.htm (ROM ADAPTER)

https://www.exxosforum.co.uk/atari/store2/#0005 (V1.5 BOOSTER)

The black PCB has now been superseded by the board below.


CE SELECT JUMPER PAD
As shown in the image above, the middle and top pads are soldered which is booster mode. This means the ROM CE signal is now done externally via the white wire which connects to the V2.3 booster. This allows the booster to operate with TOS104 or TOS206. Both versions are held in the ROM.

The bottom and middle pads select GLUE decoding, which is done normally with TOS102 & TOS104.

NOTE:
TOS206 is only usable when the V2.3 booster is installed.


UBE SWITCH
Future update planned to incorporate the UBE switch. This allows TOS version to be selected by the reset button on the machine.


SEL JUMPER
Simple jumper links to select TOS version. There will always be 2 ROM versions with this board. TOS102/TOS104 typically for the normal STFM (same operation as the black boards) or TOS104/TOS206 when used with the V2.3 booster.


STORE LINK
https://www.exxosforum.co.uk/atari/store2/#0131