Scale Communication

Cable

RS-232 Serial Communication Ports

Depending on whether the scale is wired for DTE or DCE, it may require a null modem cable or replacing and rewiring the serial connector.

Configuration

Set up the scale. 9600 baud, 8 bit, no parity

See Section Section 13 of the CPW200plus User Manual for detailed instructions.

With the scale off, hold the Tare/Zero button and press the On/Off button.

Parameter	Setting	Rational
Auto Power Off	Pr oFF	Don't want the scale to turn off after a period of inactivity.
Backlight always off	bL 1	Increases battery life when AC power fails.
Baudrate	9600	Default
8 Bit no parity	PAr 1	Default
Transmission Mode	trn 1	Default. Can set to trn 2 during trouble shooting.

Testing communication

Terminal Emulation program like Minicom

During initial testing, if trouble is encountered communicating with the scale, it may be useful to set the scale in trn 2 mode so that it continuously transmits data.

Configuring the computer's serial port

To list the line parameters for ttyS0: stty -F /dev/ttyS0 -a

Example:

# stty -F /dev/ttyS0 -a    
speed 9600 baud; rows 0; columns 0; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>; eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V;
flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 hupcl -cstopb cread clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff -iuclc -ixany -imaxbel -iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke

stty can also be used to set the serial port parameters:

stty -F/dev/ttyS0  -hupcl ignbrk  -icrnl -ixon -opost  -onlcr -isig -icanon -
iexten -echo -echoe -echok  -echoctl -echoke igncr