Serial and TX threshold help??

Dear all

I wonder if anyone can help.

I am trying to emulate a device (a radio) that transmits 32 bytes of data via the serial port periodically. These 32 bytes are transmitted in 2x16 byte groups. When using portmon.exe you can see 2 entries of 16 bytes each.

Using the arduino hardware UART although I can send exactly the same bytes they are sent ONE at a time. So on portmon.exe there are 32 lines instead of 16 lines each of one byte length. As a net result the emulation does not work.

In VB6 I can achieve the same emulation by changing the SThreshold value of mscom32 eg change this to 16. Once there 16 bytes in the buffer then all of them get transmitted.

Does anyone have a clue on how I can achieve this with arduino? My baud is 4800

Thanks in advance

Sketch?
Are you using "println" for every byte?

Groove nailed it I think. Study below the difference in using println and print in your sketches.

Lefty