BusExpanderTM - circa 1988
The BusExpander provided Zorro II and IBM PC card expansion for both theAmiga A500 and A1000 computers. It was made by Bill's Boards.
BusExpander Assemblies
The Bus Expander consisted of a motherboard which installed into a standard
IBM AT Style case of the day. A driver board plugged into the expansion slot
on either the right side of an Amiga 1000 or the left side of an Amiga 500.
High quality high speed custom ribbon cables connected the driver board onto
either the left or right side of the mother board. A bus termination card was
installed on the opposite end of the motherboard bus.
Schematics
Parts List not available - Anybody have one?
Could use the schematics to psych it out.
Original PALs are extremely rare.
These equations are believed to be correct.
The ribbon cables were custom manufactured Chabin Transmission Line Cables.
Pins 1 and 2 of the connectors are internally connected to shield conductors
which were routed between each signal conductor. There is effectively 80
conductors with every other one grounded.
Images of the Bare Boards
There are two trace errors on the termination board! The trace between C47 and J15 is wrongly connected to pin J15-12(XRDY)
The trace is removed and a jumper wire connects C47 to pin J15-8(C3B*)
A missing trace from RN16 pin 3 to J15 pin 18(A4) requires a jumper wire
There are three trace errors on the driver board!
Remove the top side trace from U8-8 to R8.
Remove the bottom side trace from U8-6 to R9.
Jumper wire from U8-6 to R8. Jumper wire from U8-8 to R9.
Remove the bottom side trace from J17-17(A6) to U2-11.
Jumper wire from J17-17 to U1-11.
It is unknown if there are any trace errors on the main board.
Miscellaneous Parts
1988 BusExpander Assembly Instructions
