ANT Forum

Thank you for taking time on my problem.
I have a custom board and am starting to implement ant+ communication through an asynchronous bus out of a pic24FJ64GB004 mcu. I send a System_Reset (A4, 01, 4A, 00, EF) after about 60Us the nRF24AP2 by Nordic Semiconductor toggles the RTS pin. The toggle is 400Us in duration and has a strange discharge in the center of it, about .7V, and then recovers back to full logic. I can continually make this happen in a loop, but the nRF24AP2 will not acknowledge subsequent commands, by indicating a 50Us toggle on RTS. Any ideas would be helpful.

Thanks
Cy Drollinger      

Hi,

After sending the "Reset System" command, the host MCU should wait at least 500 ms to ensure that ANT is in the proper state before issuing any further commands from the host.      

The 400Us assertion and the strange discharge have not been identified and the RTS line may not be a 50Us as has been described in the nRF24AP2 datasheet. My checksum value was not calculated properly using xor for each byte. The device now communicates messages and a RTS signal is being asserted from the nRF24AP2 by Nordic semiconductor. This is more or less solved      

The Checksum was not calculated properly utilizing the xor of each byte sent. Solved!