Hello,
On an #SC18IM704 Eval Board UM11664, I had observed some, for me unexpected behaviour.
For Payload of 1 Byte, I observed the transmission of 2 Bytes. And no - I am not referring to the transmission of the slave adress.
When sending certain values in payload, there is something that looks like CRC send happening which is neither expected, nor described in the manual.
What did I try:
1) I am using Clock 01d4, (4,06kHz) - But the described glitch also appeared with the default clock setting.
2) I am sending 1 Byte and observe data and clock on the scope, there is no target hardware connected to the i2c lines.
3) For all tested byte contents (see attachments for 0x00 and 0xB5 for reference) there happens exactly what I wanted and which is according to the datasheet.
4) For these two suspicous values 0xA5 and 0xC5 The "bit excess" is generated.
I read
0xA580 for payload write 0xA5 (for input via UART of 53 cc 01 a5 50)
and
0xC507 for payload write 0xC5 (for input via UART of 53 cc 01 c5 50)
Where does this come from?
Best regards, NFCbrick
