Watkins-Johnson Company WJ-8718A/MFP Instruction Supplement page 135

TABLE 4-17
TABLE 4-18
WJ-S718A/MFP
and is connected to a remote control device compatible with the 488 bus. Troubleshooting the
I/O Interface may be required when the receiver appears inoperative only during remote
operation. The interface contains two modules to support the microprocessor system. All
pertinent information for the modules is given in Tables 4-17 and 4-18. The tables are to be
used in conjunction with the information in paragraph 4.1.4.6.1.
Table 4-17. I/O Interface
ModUles
(488M-A3)
Module
Data 1 2
Description Receiver address
GPIB interface
switch
Functional Circuit S1 U1
Tri-State Buffer
U4
Internal (U1)
Buffer Clock U7, pin 15 U7, pin 14
Data Capture Latch
NA NA
Data Capture Clock
NA NA
Address Capture Latch U6 U6
Address Capture Clock
U8E, pin 10 USE, pin 10
Address Decode U7 U7
NOTE: NA denotes not applicable.
Table 4-18. I/O Interface Support Circuits (488M-A3)
Support Circui t Supports Function
U2 U1 Transceiver
U3
U1
Transceiver
U5
U4
Pull-up resistive network
USA U7 U6 output inverter
USB U1 Clock generator
USC NU
U8D U10 RESET OUT inverter
USE U6 ALE inverter
USF
U1
Clock generator
U9A NU
U9B U1 ATN disable
U9C NU
U9D
U10 Clock input
U10
U1
Transceiver direction control
NOTE: NU denotes not used.
4-24