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

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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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Contents Short-Haul Modem B SHM-B Async SHM-B Async SHM-B Async SHM-B Async Trademarks Used in this Manual Distance miles/km SpecificationsOperating Temperature 32 to 112F 0 to 50C SHM-B Async Introduction Four-Wire Connections InstallationSHM-B board 5-screw terminal block EIA-232 Connection Wiring diagram for two SHM-B unitsEIA-232 Pin Connections on SHM-B Switch SettingsPinning with DTE/DCE switch in the DCE position Flow Control ON/X-OFF Mode Operation Activating the Loopback switchSHM-B Async Rackmount Installation SHM-B Async Troubleshooting Guide SHM-B Async SHM-B Async SHM-B Async SHM-B Async SHM-B Async Copyright 2000. Black Box Corporation. All rights reserved