Salter Brecknell LPS-15 - Manual (Page 26)

24 LPS Series User Instructions
5 Serial Communication
RS-232 Connections between scale and host.
Notes:
On the indicator's DB9 female, pins 4 and 6 are shorted and pins 7 and 8 are shorted.
The baud rate and parity are configurable. Parity, start (low) and stop (high) bits will
each be fixed at one. Data bits will be fixed at seven (if no parity bit, the data bit is eight).
Modem lines will not be supported. Baud rates supported will be 1200, 2400, 4800,
9600 and 19200. Responses to serial commands will be immediate, or within one
weight meter cycle of the scale. One second should be more than adequate for use as
a time-out value by the remote (controlling) device.
The length of the weight field will be 10 bytes (for 5 1/2 LCD): one for minus sign, one
for decimal point, two for unit of measure (e.g. "lb", "kg"), six for weight data; The
leading zero in weight data will be suppressed.
l If the weight is overcapacity, the scale will return eight '^' characters (the field
of minus sign, decimal point, weight data is filled by '^').
l
If the weight is under capacity, it will return eight '_' characters (the field of
minus sign, decimal point, and weight data is filled by '_').
SP.X is the serial protocol of RS-232:
l
If weight is negative, in motion, the scale will still respond with a weight and
status string.
l
If the weight is overcapacity, the scale will return eight '^'. If the weight is
under capacity, it will return eight '_'; if the zero point is error, it will return
eight '-'.
l
Units of measure abbreviations are always lower case.
l
The weight may be negative; therefore a polarity character is present. The
character will be '-' for negative weight or a space character for positive
weight.
l
Weight field is always eight characters (6 for weight, 1 for decimal point, 1 for
polarity).
l
Leading zeroes are suppressed.
Indicator Cable Host
(DB9 female) (DB9 male) (DB9 female) (DB9 male)
TXD 2 2 2 2RXD
RXD 3 3 3 3 TXD
GND 5 5 5 5 GND
DSR 4 4 4 4 DTR
DTR 6 6 6 6 DSR
CTS 7 7 7 7 RTS
RTS 8 8 8 8 CTS
NC 1 1 1 1
NC 9 9 9 9