Total Control MP/16, Руководство оператора, Страница: 158 / 182

E-8 Modem Testing
4
Reset DIP switch 9 OFF unless you normally operate with it
ON. Issue an ATZ command to initiate the new switch setting.
Reset the modem to &M4 unless you've sent it the ATZ reset
command.
Testing With Register S16
Register S16 is a bit-mapped register with the following bit
functions:
Bit Value Function
0 1 Analog Loopback (AL)
1 2 Dial Test
2 4 Test Pattern
3 8 Remote Digital Loopback (RDL)
NOTE:
Earlier U.S. Robotics modems require bit 3 to be enabled
in order to grant RDL to a remote modem. The modem now
requires its default &T4 setting instead. To perform RDL with a
U.S. Robotics modem that does not use the &T test repertoire, that
modem should be set to S16=8 before it can grant RDL testing.
Analog Loopback (AL)
 
S16=1D
As with the &T AL test, do not attempt this test under error
control. MP modems should be tested at 2400 bps or lower, to
avoid asymmetrical modulation at higher speeds.
1 To initiate testing, type AT&M0S16=1D. The modem disables
error control, enters AL mode and sends a CONNECT result
code. The Modem LED glows green.
2
Type data to the modem for the modem to transmit, loop to its
receiver, and output to the screen. An alternative is to use the
Test Pattern , described later.
3 End the test by not typing anything for one second, then typing
three pluses (+++), and waiting another second. This forces the
modem back to Command mode. If DIP switch 9 is OFF, the
modem exits AL mode and returns to Command mode. If DIP
switch 9 is ON, the modem maintains the connection when it