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Operation
Xerox FS 3270, User's Guide
3. Operation of Xerox FS 3270
The Xerox FS 3270 top panel has been designed to register the operation of the box via the four following indicator LEDs :
∙CU (contact to Control Unit)
∙PAR (parallel input)
∙SER (serial input)
∙READY (printer)
3.1.The Indicators of the Xerox FS 3270
CU (Contact with Control Unit)
This indicator LED has 3 states:
State | Indication |
ON | Contact with the control unit. |
BLINKING | 1. Contact with the control unit, and data pending |
| in the Xerox FS 3270 buffer. |
| 2. Indicates that the TEST switch has been |
| activated and the box is ready to enter |
| HEX dump mode |
| 3. The CU indicator will be blinking rapidly while |
| the rotary switch is in the “T” position. This is an |
| indication that the “T” position is not a valid |
| permanent position. |
OFF | No contact to the control unit, or the contact has |
| been broken for more than 1 minute. |
PAR (Parallel input)
The indicator LED has 2 states:
State | Indication |
ON | Indicates that the box is processing data from the |
| Centronics parallel port |
OFF | Indicates that the box is idle or processing data |
| from the coax/RS inputs |
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