TOS206 ST DECODER BOARD - 68K type

[exxos]

V1_PCB.jpg

A compact TOS104 / TOS206 decoder board which can plug(or solder) into any existing 68000 socket. It also has the ability to have a socket on top for a CPU or accelerator.

REVISION 1- First prototype production run which has TOS decoding only (the PCB will mention 16MHz but it is not included on that version)


FITTING to H4 MOTHERBOARD

The decoder board will work in any of the H4's expansion sockets.

Solder a wire ( if not already fitted ) to the CE pad near the top left of the board.

V1.JPG

On the H4 remove JP13 Jumper and connect the other end of the CE wire to the right pin.
(Removing this jumper isolates the GLUE's ROM CS signal from the ROM so we can drive it from the decoder board instead)

IMG_5148.JPG

Assuming you have already a DUALTOS ROM fitted to the H4, you can select bank 1 or 2 by removing or fitting JP1.

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68K SOCKET USAGE (H4 & ORIGINAL ST MACHINES)

v1socket.jpg

A DIP 68000 be used in the socket for original or H4 motherboards. The socket can also be used to plug in accelerators or boosters. The decoder board also correctly handles the bus grant logic for accelerators.



FITTING TO ORIGINAL ST MACHINES.

While the socket can still be used as stated above, if no accelerator or other add-ons are to be used, it is recommended that the CPU be soldered directly onto the decoder board because there is some height restrictions on various STF machines

Also note that using original machines you will also need a DUALTOS ADAPTER. Wire CE wire from the decoder board solders to the CE pad on the DUALTOS board.

NOTE - I only produce DUALTOS adapter boards which will fit the 70789 style boards and MEGA ST.


LINKS

STORE LINK
https://www.exxosforum.co.uk/atari/store2/#0172

DUALTOS ROM (104 & 206)
https://www.exxosforum.co.uk/atari/store2/#0054

STFM 70789 DUALTOS ADAPTER
https://www.exxosforum.co.uk/atari/store2/#0131

MEGA ST DUALTOS ADAPTER.
https://www.exxosforum.co.uk/atari/store2/#0008