Black Box Short-Haul Modem B, ME810, ME800A-R2, ME805-C-R2 manual SHM-B Async

SHM-B ASYNC

Pins 4, 5, 6, 8, and 20 should all be HIGH to enable communication.

5.If pin 8 (Carrier Detect) is low, this indicates:

•a defective transmission line or connection

•a defective remote SHM-B

•remote SHM-B without power

SYMPTOM: TD and RD LEDs indicate data activity, but data communication doesn’t exist.

1.Check the wiring of the EIA-232 port. Refer to Section 3.2 for information.

2.Check the setting of S1. Refer to Section 3.3 for information.

SYMPTOM: Transmitted and/or received data is full of errors (garbled data).

1.Check for reversal of polarity on the four-wire connection. Refer to Section 3.1 and Figure 2.

2.Check word structure and speed settings on your

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