Help with "Break Command"

mkb72

I am trying to control a 360 Systems Digicart E using an NI-700 over RS-422. I've had very little success and after a lot of time on the phone with 360, they're convinced that I may be sending the wrong kind of break command before each play command. I have been using the code taken directly from the AMX website which shows the break command as:

(*** Send Break character ***)
SEND_STRING DEV,"27,17,10"

The Digicart E manual describes the break command as follows: "The Break character is defined as a minimum of 20 bits Space followed by a minimum 2 bits Mark. It is used to synchronize all devices connected to the interface bus."

Can anybody out there tell me if they see what I am doing wrong? Is this break command actually the source of my problem or is this correct and I can start looking elsewhere for the issue? Anything would help.

Thanks,
Mike

jweather

Try a longer time parameter (the third number). A time of 10 = 10 * 100 microseconds = 1 msec. The protocol specifies a minimum of 20 bits, which would be just over 2 msec at 9600 baud if my math is correct. I would probably try a time of 100 to see if it did anything. 10msec isn't going to slow anything down too much.

dthorson

SEND_STRING dvSWT,"27,17,60,$30"

I've uses this on a DataVideo switcher. The $30 may be those min 2 bits the device is looking for.

jweather

dthorson wrote: »

SEND_STRING dvSWT,"27,17,60,$30"

The 60 is the duration of the break (6 msec). $30 is ASCII for 0.