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Communication protocol
#1
I now have a Java interface to the PPMAC up and running that uses an SSH library to connect to the host and then opens a "session" to start a shell and execute the gpascii command. I have IOStreams for the stdin and stdout streams of the gpascii process and am successfully able to send commands and parse the responses.

BTW: I am seeing command responses in the form:

<command echo><CR><LF><response><CR><LF><ACK><CR><LF>

I have not yet tried a command that returns multiple data packets, but based on the above I would imagine it looks something like this:

<command echo><CR><LF><response1><CR><LF><response2><CR><LF> . . . <ACK><CR><LF>

It would be really nice if you guys could document this someplace (I haven't found it in any of the manuals yet).

Also: I notice that the PPMAC IDE uses a "-2" option when starting a gpascii connection. What is that for? unfortunately, gpascii does not even have a --help or --? option, so I cannot tell what it means.

//-------------------------------------------------------//

The command echo is controlled by the on-line command echo. It is session dependent. Details are in the PPmac on-line command manual.

gpascii -2 is a mode that allows the sendng ofuser variable names. In my project I can declare a variable as

global myvar1;

We will auto-assign this to a p-variable. From a host program you do not need to know how this was assigned when using gpascii -2 you just send myvar1 and gpascii will find which p-var was assigned to myvar1 and will ask pmac for the correct value and report back the data.

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