Avago Technologies LSI53C120 - Manual (Page 34)

3-4 Specifications
3.1.3 SCSI A Interface Pins
Table 3.1 lists the SCSI A side interface pins associated with the 128-pin
Plastic Quad Flat Pack (PQFP).
Table 3.1 SCSI A Signal Description
SCSI A Pin Type Strength Description
A_SD[15:0] 8, 6, 5,
4, 36,
35, 34,
32, 19,
18, 16,
15, 14,
13, 11,
10 I/O 48 mA Data (16-bit SCSI bus)
A_SDP/(1-0) 9, 20 I/O 48 mA Data parity bits
A_SCD/ 29 I/O 48 mA Phase line, command/data
A_SIO/ 31 I/O 48 mA Phase line, input/output
A_SMSG/ 26 I/O 48 mA Phase line, message
A_SREQ/ 30 I/O 48 mA Data handshake signal from target device
A_SACK/ 24 I/O 48 mA Data handshake signal from initiator device
A_SBSY/ 23 I/O 48 mA Bus arbitration signal, busy
A_SATN/ 21 I/O 48 mA Attention, the initiator is requesting a message out
phase
A_SSEL/ 27 I/O 48 mA Bus arbitration signal, select device
A_SRST/ 25 I/O 48 mA Bus Reset