Plus/4 Parallel Port I/O question

From: Larry Anderson (
Date: 2000-07-24 05:27:54

Since I have some time to write stuff up, I am documenting wiring and
usage of the Flash Attack cable (a PET-to-PET data cable), and am
adapting it to the other 8-bits (64, VIC, Plus/4, etc.) This cable I
have quite a bit of coding experience on, from easy BASICable
send/receive routines to memory movers, (should adaptable to the other
cable, since the I/O code is separate from the main routines.)

I have notes that the Plus/4 Parallel Bus Pins are (a mess):

 B   Parallel Data Line bit 0
 K   Parallel Data Line bit 1
 4   Parallel Data Line bit 2 (also 'cassette sense', unplug datasette
before use)
 5   Parallel Data Line bit 3   
 6   Parallel Data Line bit 4
 7   Parallel Data Line bit 5
 J   Parallel Data Line bit 6
 F   Parallel Data Line bit 7

and the 'address' for the port is 64784 ($FD10)

but I cannot find an entry for the cooresponding Data Direction Register
which assigns the bits as input or output....  :/  

Also on a side note, anyone have the B-128 Parallel Port and DDR
locations, I assume the pinout positions are similar the the VIC and C64?

01000011 01001111 01001101 01001101 01001111 01000100 01001111 01010010 01000101
   Larry Anderson - Sysop of Silicon Realms BBS  (209) 754-1363 
300-14.4k bps
     Classic Commodore pages at:
01000011 01001111 01001101 01010000 01010101 01010100 01000101 01010010 01010011
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