Device suitable for my application?


Hi all,

I was wondering if the Fastrack Supreme is suitable for following apllication: I want to communicate with a device over RS232, and send data to a server over TCP. The most demanding part of the modem will be the handling of the serial communication. The modem has to send packets to the device, but with a small delay between the sent bytes (± 10 ms). After, the device will respond by sending another, larger packet, with a CRC at the end. The modem must calculate the CRC, and do some retries if necessary. Afterwards, all packets will be assembled to a bigger data packet of about 12K. Again a CRC has to be calculated. This complete data packet will be send to the server. In certain situations, the modem will receive all data at once (at 9600 bps). So my questions are:

  • Is it possible to create a small delay between the sending bytes
  • Is the receive buffer of the serial port large enough to handle a stream of 12K at 9600 baud?
  • Is the processor fast enough to calculate a CRC in a short time? I tried it on another platform based on pythonscript, which costs me about 4 minutes for the calculation. (the 12K packet)

The main problem concerning the module based on pythonscript is the processing speed. The delays caused by the CRC calculations and a minimum delay of 100 ms between the sent bytes are unacceptable.

Kind regards,



The basic Open-AT timer resolution is 18.5ms - so it depends on how precise these delays need to be.

Not the serial port itself - but your application could easily do this.

Yes - especially if you do a “running” CRC as the data is received.

That must have been a grossly inefficient implementation! :open_mouth:

No kidding!! :open_mouth: