Specifications

CHAPTER 1
Overview of LaserWriter Pro Hardware
Internal SCSI Connector 11
Table 1-7 Signal descriptions for internal SCSI connector
Pin number
Signal
name Description
1, 2, 24 +5V +5 V power supply
3, 4, 5, 7, 9,
11, 13, 15,
19, 21, 23,
27, 31, 35
GND Ground
6 /DB0 Bit 0 of SCSI data bus
8 /DB1 Bit 1 of SCSI data bus
10 /DB2 Bit 2 of SCSI data bus
12 /DB3 Bit 3 of SCSI data bus
14 /DB4 Bit 0 of SCSI data bus
16 /DB5 Bit 0 of SCSI data bus
17 Open Open line.
18 /DB6 Bit 0 of SCSI data bus
20 /DB7 Bit 0 of SCSI data bus
22 /DB8 Parity bit of SCSI data bus
25 /ATN When active (low) indicates an attention condition
26 /BSY When active (low) indicates that the SCSI bus is busy
28 /SCSIACK Handshake signal; acknowledges a request for data
transfer
29 /RST SCSI bus reset
30 /MSG When active (low) indicates the message phase is
active
32 /SEL Selects between target and initiator
34 /C/D When active (low) indicates that data is on the SCSI
bus; when high indicates that control signals are on
the bus
36 /REQ Request for a data transfer
37, 38 MGND Memory ground
39, 40 Motor5V +5 V power supply for motor