PT PT200MI - RS232;RS485 Input;Output (Optional)

PT200MI instruction manual 27
8.3 RS232/RS485 INPUT/OUTPUT (OPTIONAL)
Refer to the appendix if installation of the option is required.
Refer to page 7 for the rear panel connection diagram.
Schematic diagram of the serial port.
Handshake looping a PC serial connector
8.3.1 RS232/RS485 COMMUNICATION PARAMETERS
Parameters are set in the function setting stage, section 5.
Baud rate : 2400, 4800, 9600, 19200 Data bits : 7 bits
Stop bit : 1 bit Parity bit : 1 (even)
Code : ASCII Delimiter : CR/LF
8.3.2 COMMUNICATION MODE
Two modes are available for weight output. Continuous and polled or command. The command
mode also enables output of other values and configuration of the PT200MI.
Continuous mode:
(1) Outputs the weighing data continuously in a pre-defined format shown above.
(2) The output rate is in accordance with the BCD update setting times.
Select 4, 8, 16 or 20 times/sec at 19200 baud.
Select 4, 8, 16 or 20 times/sec at 9600 baud.
Select 4 or 8 times/sec at 4800 and 2400 baud.
Command mode:
In command mode a command is sent to the PT200MI and a response is received back. The commands
vary upon the operational mode and are listed below.
Command input PT200MI response Description
READ<CR><LF> ST,GS,+ 1234kg<CR><LF>
ST,NT,+ 200kg<CR><LF>
Weight data is output, output is gross
data (GS) when the display shows gross
weight and net data(NT) when the
display shows net weight
TARE<CR><LF> TARE 12345<CR><LF> Responds with the tare weight.
TARE ON<CR><LF> YES<CR><LF> or NO ? <CR><LF> Sets tare. Tares the current reading
TARE OFF<CR><LF> YES<CR><LF> or NO ? <CR><LF> Resets tare.
TARE [num]<CR><LF> YES<CR><LF> or NO ? <CR><LF> Set tare (max. cap. tare value).≧
ZERO<CR><LF> ZERO 1234<CR><LF> Responds with the zero value.
ZERO ON<CR><LF> YES<CR><LF> or NO ? <CR><LF> Zero return range is 1% to 10% of
max. capacity, the same action as
pressing the zero key.
ZERO OFF<CR><LF> YES<CR><LF> or NO ? <CR><LF> Resets the zero offset.
KEY<CR><LF> KEY ON<CR><LF> or KEY OFF<CR><LF> Key protection state.
TXD
RCD
TXD
RCD
COM
RS232
(+)
(-)
RS485
While the normal PC hardware might well run with just Tx, Rx
and Ground connected, some driver software will wait forever
for one of the handshaking lines to go to the correct level.
Depending on the signal state it might sometimes work, other
times it might not. The reliable solution is to loop back the
handshake lines if they are not used. Connect
PT200MI terminal 10 to DB9 Pin 2,
PT200MI terminal 11 to DB9 Pin 3,
PT200MI terminal 12 to DB9 Pin 5.