okwatts wrote:
OKay I have attached the text print out of the prom,which indicates it exactly mirrors the default memory map for the SYM. The outputs are chip selects for the controller's i/o map. $9000 for the eprom, $f000 for the fdc controller and $f100 for the control port. The outputs are low for the chip select for the various chips. You have 256 locations for the 256 pages of memory in the memory map. Hope it helps.
That's awesome! Thank you so much for providing that. This confirms I have a custom PROM installed which seems to be setup as the following:
Code:
A600 = Hex Latch,Buffer // 1110 E
A700 = 1791,Buffer // 1000 8
A800 = disabled // 1011 B
A900 = EPROM // 0011 3
AA00 = EPROM // 0011 3
AB00 = EPROM // 0011 3
AC00 = disabed // 1011 B
AD00 = EPROM // 0011 3
AE00 = EPROM // 0011 3
AF00 = EPROM // 0011 3
1011 -- /Data Bus Buffer
|||____ /CSEL 1791
||______ Side Sel,DS1,DS2,Motor On Hex Latch (active high)
|_______ /EPROM
I was looking at pics online of various machines and noticed that this AIM-65 has a FDC-1 installed
interesting...
Thanks again for the help!