Serial Port Configuration Problem (SerialPortX 2.1 library)

Question

First, thanks to the author for all of the hard work on this AppleScript library. It has worked sucessfully for me for the last two years.
However, I'm having a problem with a new-to-us scale in our laboratory. It's an older model and requires the communications settings to be 9600 / 7-E-1 with no handshaking. For novices such as myself that's 9600 bits per second, 7 data bits, even parity and 1 stop bit. I am able to successfully communicate with the scale via screen in Terminal or Serial Tools v0.4. The scale is physically attached to my Mac using a KeySpan USA-19HS serial to USB adapter.
By connecting my mac to a PC I've been able to successfully communicate between the two machines with an AppleScript using the SerialPortX library as long as all parameters match (e.g., bit rate, parity, stop bits and handshaking). The only time this fails is if the data bits is anything other than 8, which makes me think that a bug is preventing me from changing the default value (in my scale's case from 8 to 7).
Has anyone had any experience with this error? Is it possible to edit the script library to change the default to 7? Any other possible work-arounds (remember the scale is old and I can change the data bits on it)?Any advice or follow up questions are appreciated. Thanks for your time and consideration.

Answer 1

Thanks for the suggestion. Here's my AppleScript:
set {lf, cr} to {ASCII character 10, ASCII character 13}
set carriage_return to (cr & lf as Unicode text)
set myport to serialport list
set oh to choose from list myport
set PR to serialport open oh bps rate 9600 data bits 7 parity 2 stop bits 1 handshake 0
set cmd to "Q" & carriage_return
if PR is equal to -1 then
display dialog "could not open port "
else
serialport write cmd to PR
delay 10
set mystr to serialport read PR --for 30
delay 1
#set cmd to "OP" & lf
serialport close PR
end if
display dialog mystr