User`s guide

22
RS232
The RS232 card provides two functions. It provides RS232 ports, and it acts as a bridge to an FDX
box (even if you don't have one connected). As a consequence, if the MTX tries to read ROM 4 or
ROM 5, or input from ports 20H or higher, or if it detects DMA from the FDX, it will drive the MTX
data bus. This is clearly incompatible with an SDX, and its incompatible with REMEMOrizer too. An
SDX and REMEMOrizer have their own ROMs and ports at these locations.
Therefore, if you have an RS232 card, remove its PAL (IC8 on the RS232 board), and replace it with
the serial GAL supplied with REMEMOrizer. This prevents the RS232 card from acting as a proxy for
an FDX which doesn't exist.
Warning: Do not attach REMEMOrizer to an MTX with an RS232 card if you have not replaced
the PAL. Both the RS232 card and REMEMOrizer will attempt to drive the bus at the same
time, which could result in permanent damage to the RS232 card and/or REMEMOrizer.
Note: Should you want to disconnect REMEMORizer and reconnect to an FDX, the replacement PAL
mustbe removed and replaced with the old RS232 PAL.
PLUG IT IN
Double check the ROM and MTX500 jumper positions as well as the ROM and GALs fitted.
Connect the REMEMOrizer board to the connector on the left hand side of the MTX.
Connect a VGA monitor to the 15 pin D-sub connector at the top right of the REMEMOrizer.