Connector Descriptions Appendix D
VXI-MXI User Manual D-2 © National Instruments Corporation
The MXIbus defines 49 active signals, 12 ground lines, and 1 line for terminator power. Table
D-2 describes the signals on the MXIbus connector and groups them in five categories.
Table D-2. MXIbus Signal Groupings
Category Description Signal Name Lines Pin Numbers
Address/Data Address/Data AD[31-00]* 32 6-37
Address Modifier AM[4-0]* 5 1-5
Address Strobe AS* 139
Transfer Size SIZE* 144
Read/Write WR* 140
Data Strobe DS* 138
Data Acknowledge DTACK* 141
Parity PAR* 143
Arbitration MXIbus Busy BUSY* 146
MXIbus Request BREQ* 145
MXIbus Grant In GIN* 160
MXIbus Grant Out GOUT* 159
Interrupt Interrupt Request IRQ* 161
Utility MXIbus Error BERR* 142
Power Ground GND 12 47-58
Terminator Power TERMPWR 162
Notice that there are 12 ground contacts on the connector. The 48 twisted ground lines in the
cable are generated from these lines under the cable connector hood. Also notice that although
there are two connector contacts required for the GIN*–GOUT* daisy-chain, only one signal line
is required in the cable assembly.
For more information, refer to the MXIbus specification.