Commodore Amiga A500 Technical Reference Manual page 173

40142 WRITE READ
*HCBP bit
not defined
not defined
not defined
not defined
Interrupt enable
DON'T .CARE
MUST BE ZERO
*CCBP bit
INT2 PENDING
ZERO
ZERO
INT FOLLOW
*
Signals unique to Amiga Hard DisWSCSl Controller.
SSEL Used to select SCSl controller or t o ST605
controller. High
=
SCSI, low
=
ST506.
HCBP,CCBP Host command block pointer and Controller
command block pointer. Used t o handshake
address of Command block pointer t o ST506
48H Base address register
U0 addresses unique to
501-1
board
SCSI Controller
PROCC-Interrupt ST506 controller t o process
command. Write only. Data value written from
host is XXX1 hex.
WRCBPJINTACK
-
Multiplexed signal. WRCBP
strobes the command block pointer register.
IN-
TACK clear INTP a t end of command.
CS
-
Chip select for the WD33C93 SCSl chip.
Used to write t o the internal address register and
read from the internal status register.
CS
-
Chip select for the WD33C93 SCSl chip.
Used t o write and read remaining Control regis-
ters in the WD33C93.
SCSl PCSS
-
Used to initialize the 8727(DMA) in
SCSl mode. Refer t o section 5.0 for 8 7 2 7 com-
mands
SCSl PCSD
-
Used t o pas data t o and from the
8 7 2 7 in SCSl mode. Refer t o section 5.0 for
transfer procedures.