Switch package SW2 (Figure 12) performs two functions:
l
It selects either RS232C or 20-mA current loop operation FOR BOTH PORTS ON THE RS232C BOARD.
AND
l
It selects the status of the DATA TERMINAL READY (DTR) signal for each port.
Figure 12 illustrates all settings for SW2. A summary of DTR settings is provided below.
MODEL 43 TELETYPE, G.E. TERMINEI-TE,
ADDS CRT, LOCAL PRINTER, CASSETTE
1
Port 1,3, or 5: switch 4
TAPE UNIT
Any device requiring DTR to be
normally HIGH (LOW when busy)
or
Any device NOT using DTR signal
CENTRONICS 150
or
Any device requring DTR to be
normally LOW (HIGH when busy)
UP
UP if port 2,4, or 6 is 26-mA Current
loop
Port 2, 4, or 6: DTR normally HIGH
(LOW when busy) switch UP
UP lf port 1,3, or 5 is 2O-mA Current
loop
Poti 1, 3, or 5: DTR normally HIGH
(LOW when busy) swttch UP
J
is UP (toward IC16)
Port 2,4, or 6: switch 2
is UP (toward IC16)
1
Port Port
is DOWN (toward IC8)
2,4, 1,3, or or 5: 6: switch switch 4 2
is DOWN (toward IC8)
DOWN
DOWN if port 2,4, or 6 is RS232C
Port 2, 4, or 6: DTR normally LOW
(HIGH when busy) switch DOWN
DOWN it port 1,3, or 5 is RS232C
Port 1, 3, or 5: DTR normally LOW
(HIGH when busy) switch DOWN
FIGURE 12
NOTE: UP = toward IC16
DOWN = toward IC6
Switch packages SW3 and SW4 are used to address the RS232C ports.
Set the switches on SW3 and SW4 as
indicated in Table G below and on page 20.
TABLE G
1 BOARD# i PORT# i
SW3
I
SW4 I
1
2
1
All switches UP
CLOSE switches 2,3, and 7
2
(toward R12)
OPEN switches 1,4, and 8
3
All switches DOWN
CLOSE switches 1,4, and 7
4
(towards CONV2)
OPEN switches 2,3, and 8
I
3
I
:
I
All switches DOWN
I
CLOSE switches 1,4, and 8
(toward CONV2) OPEN switches 2,3, and 7
I
Note: Port 1 is always dedicated to the BMUX local printer.
19
To Next Page
Loading...