NMIY0020's MEMDIS signal = HOWTO ??

[blitz119D]

Hi,
from the schematic diagram of NMIY0020, the MEMDIS signal is default to pullup to +5V and if I install the Buffalo Monitor on say U3 socket and I connect chip select H6 which is from U8 chip( AT18V82 ) to enable
my external MC6821 PIA chip then does this MEMDIS
signal will disable my MC6821 chip & make it not in my memory Map ???? I am considering to bypass this MEMDIS signal ? Would appreciate your inputs on this
MEMDIS issue .... Abraham Wong

[nmitech]

First, The Buffalo monitor must install on socket U4 and Max-FORTH operating system must disable in order to run the Buffalo monitor.

H6 is the spare chip select (0xB0C0 - 0xB0FF), active low signal decodes from the PAL U8. This signal is specificly decoded to interface with peripheral device, So you should be able to connect to your PIA chip direct. No need to disable or bypass anything and its addresses are already decoded to avoid overlap with the memories on board.