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Proton Products SL mini and SLR mini Series Speed and Length Gauges Instruction Manual - issue 1s
RS-232
C
OMMUNICATIONS
This RS-232 interface is fitted as standard. It operates independently of the other communications
interfaces and may be accessed at the same time as them.
If the RS-
βγβ interface “Mode” is set to “
ZM400 Printer
”, then a
Zebra ZM400 printer may be
connected to the port
to print reel report tickets when triggered by the “End of Reel” logic input.
RS-232 interface
The RS-232 interface may be accessed through the following pins:
Connector type: DB25 female (socket)
Functional
group
Pin Designation
Description
Notes
PC DB9 serial
port pin
Shield
S
Shield
Shield
Connect to cable and
connector shields
Shield
Power
supply and
ground
2
DGND
Power supply
and signal
ground (0V)
5
15
24
RS-232
16
RXD
RS-232 receive
3
17
TXD
RS-232 transmit
2
The above table also shows the configuration of a cable for connection to a personal computer (PC)
type DB9 serial port.
The maximum baud rate depends on the cable capacitance and length. For low-cost overall shielded
cable with total capacitance of shield to core-plus-core to core of 300pF per metre, the maximum
recommended baud rates are as follows:
Cable length range / m
Maximum Baud rate / s
0
3
115200
3
10
38400
10
20
19200
20
40
9600
40
80
4800
1
1
4
2
1
5
3
1
6
4
1
7
5
1
8
6
1
9
7
2
0
8
2
1
9
2
2
1
0
2
3
1
1
2
4
1
2
2
5
1
3
