2.3 MODEM CONFIGURATION JUMPERS
The Modem provides six hardware configuration jumpers. Refer to Exhibit 2-3. The configuration
jumpers are described as follows:
Exhibit 2-3: Modem Configuration Jumpers
J2
Constant Power Jumper:
When installed, the modem is set to be constant powered. When
removed, the modem remains in a stand-by power mode until the MPC* input (J5-3) is set
low or the modem receives a call.
J7
RS-232 PWR Jumper:
When the alternate power connection is made through the RS-232
connector (J4), this jumper must be installed. Remove this jumper when the primary power
connection is made through the power connector (J5).
J8
Memory Write-Enable Jumper:
This configuration jumper provides a hardware safety
feature, preventing the non-volatile memory from being overwritten when an AT&Wx or an
AT&Zn=s command is accidently issued to the modem. To change the contents of the non-
volatile memory (destroying the old data), jumper J8 must be installed before issuing the
AT&Wx or AT&Zn=s command. This jumper is not normally installed.
11
J9
Delay Select Jumpers (5 Sec./20 Min.):
In the normal five-second operation (jumpers
