TMC2240 Address Confusion

Question

Hi, 
 I am looking at using the 1-wire uart for the TCM2240 but to me is unclear the address value. I am using just two devices so I can fix the address 
 As far as I understand you can set the address between 0 and 7 (so 0b000 to 0b111) so your 8-bit node address in the device can be any from 0b00000000 to 0b00000111. However, I see this also as NODEADDR. Do I need to write this in NODECONF or does this automatically get updated from the pin's status on start-up? 
 
 I would also like some clarification on this phrase: 
 EACH BYTE IS LSB&hellip;MSB, HIGHEST BYTE TRANSMITTED FIRST 
 
 So first you should send the sync nibble, then the reserved then NODEADDR then R/W+7bit register address and the data and CRC but within each byte you send MSB then LSB? 
 
 Do you offer some sample/example code for this uart interface?

BernhardDwersteg · Answer

Hi, 
 correct, the nodeaddress becomes set by the pins automatically. No need to write a different address. The bit order is standard UART bit order - you just need to make sure that you send the correct byte sequence using 8 Bit and one stop bit. Use the CRC calculation from the IC datasheet. For a library fitting your CPU, I would search GitHub for Trinamic or Trinamic UART. There you find a number of implementations. 
 
 Hope this helps.

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TMC2240 Address Confusion