25 nIDE Chip
Select 0
IRRX2
26 nIDE Chip
Select 1
IR Transmit 2
20 CLOCK 14
nHDCS0
O24P This is the Hard Disk Chip select
(Note 1) corresponding to the eight control block
addresses.
IRRX2
nHDCS1
I
O24P
(Note 1)
Alternate IR Receive input
This is the Hard Disk Chip select
corresponding to the alternate status register.
IRTX2
CLK14
Alternate IR transmit output
O24P
MISCELLANEOUS
ICLK The external connection to a single source
14.318 MHz clock.
13