Re: slots

[Wayne Stewart <waynes@intergate.bc.ca>]

They're similiar but they aren't exactly the same.
On a II or II+
slot 0 lacks I/O select and only slot 7
has Color ref on pin 35 and Video Sych on pin 19
Other than that the slots are identical

On the IIe
slot 1 pin 19 is CLKEN and 35 is ENKBD
on slot 7  pin 19 is Video Sych and pin 35 is Video Reference.
On slots 2-6 pins 19 & 35 aren't connected.
On the original Rev A board pin 23 on slot 7 isn't connected.
Also if a card is in the Auxiliary slot then I/O select to slot 3 is
inhibited.

On the IIgs ROM1
Slot 1 pins 27 & 28 (DMA IN & INT IN) aren't connected.
Pin 35 is the Mega 2 bank 0 signal on slot 3 while on slot 7
          it's Color Ref, On the other slots its not connected.
Pins 23 & 24 (INT OUT & DMA OUT) aren't connected on slot 7
Pin 19 is Color Sych on slot 7 and not connected on other slots.

The ROM 3 is the same except
pin 35 has M2B0 on slots 1-6



Keep in mind though that it's become customary to place certain
cards in certain slots and a lot of software will expect it there and
often not accept any other slot. For example it became customary
almost from the beginning to put the 80 column card in slot 3 and
there probably aren't many programs that'll accept it anywhere else

      Wayne

Jorge Canelhas wrote:

> arent all slots alike, except for the slot3 ???