Racal Instruments 1260-82, User Manual

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1260-82 User Manual
Module Operation 3-7
205C0F ERROR LED Control Register
Switch Data Write
Register
When a channel is closed, the COM n input for the relay is
connected to the CH n1 (Normally Open) output (n=channel).
When a channel is opened, the COM n input is connected to the
CH n0 (Normally Closed) output (n=channel).
Each channel of the 1260-82 is controlled by a single bit within
the Relay Control Register. When the bit is set to a 1, the
corresponding channel is closed. When the bit is set to a 0, the
corresponding channel is opened.
The Relay Control Register may be read as well. When the
control register is read, the module returns the detected position
rather than the commanded position. If the detected position is
NOT the same as the commanded position, after the 15
millisecond settling time, then an error may have occurred. When
the firmware controls the operation of the relays (message-based
mode), this will result in the illumination of the ERROR LED if
confidence mode is enabled. When register-based control is
used, the programmer is responsible for controlling the ERROR
LED.
The Relay Control Register bit assignments are shown below and
also in Appendix A.
Control Register is located at (Module Base Address) + 5
Relay
Control
Register Bit
Channel COM Channel OPEN
Connects
COM To
CLOSE
Connects
COM To
0 (LSB) 0 COM 0 CH 00 CH 01
1 1 COM 1 CH 10 CH 11
2 2 COM 2 CH 20 CH 21
3 3 COM 3 CH 30 CH 31
4 4 COM 4 CH 40 CH 41
5 5 COM 5 CH 50 CH 51
6 N/A N/A N/A N/A
7 (MSB) N/A N/A N/A N/A