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OPERATION
3.11 RS-232
INPUT/OUTPUT(I/O)
3.11.1 INTRODUCTION
This function is designed in accordance with EIA RS-232 specifications and provides the
electrical interface between the TM7000 TGG/T and a RS-232 serial interface.
In this section, all the RS-232 commands are listed. However, the assemblies that they are
addressing may be optional.
Connection to the RS-232 interface is via the rear panel 9-pin "D" connector (J2). Input data to
this interface is accepted through TXD and output data from this interface is transmitted through
RXD. Please refer to Chapter One for the pin assignments.
For Menu operation and the selection of BAUD rate, parity, number of stop bits, word length and
output format, see Section 3.7.17 (this Chapter).
*** CAUTION ***
When using this RS-232 I/O for set up control, the local (front panel LCD and switch)
controls should not be used simultaneously to set up the same function. This could lead to
erroneous or incompatible commands. It should also be noted that after having used the
RS-232 I/O for set up control, this configuration can be overwritten by the local controls
Note:
The handshake lines DTR, DSR, RTS AND CTS are used in this assembly. If not
required by the user, DTR and RTS (both options) must be pulled up through a jumper to
pin 11 in the connector.
Terms followed by “/” designate active Low signals.
*** WARNING ***
If the handshake lines are not used, then it may be necessary for the user to program a delay
of up to 10 milliseconds between consecutive characters sent from the computer to the
TM7000 to allow sufficient time to process each character before the next one is received.
One of two possible output formats can be selected, either ASCII or PACKED-BCD. The
character length is always eight bits if PACKED-BCD output format is selected, while either
seven bit or eight bit character length may be selected if the ASCII output format is used. The
input character length is always the same as the output character length.
Symmetricom, Inc.
TM7000 TymMachine TCG/T (Rev D)
3-27