What should the MSB and LSB be for the "Enter Bootloader" packet?

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cross mob
Anonymous
Not applicable

I'm having an issue with the checksum not working for the first packet in making a custom UART,per the Psoc 3, Psoc 4, Psoc 5LP and Psoc Analog Coprocessor UART Bootloader page 33-35 http://www.cypress.com/file/45171/download . This packet only contains start, the enter bootload command,the checksum for those two commands and the end command.The checksum should be the two's complement of the LSB and MSB for the addition of 0x38 and 0x01 which is 0x39 but for some reason the psoc is responding with incorrect checksum or 0x08. The current values that I am using are 0x07 for the LSB and 0x0C for the MSB. If  anyone has an idea on what the issue may be please reply.

-Thanks

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himam_31
Employee
Employee
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Hello ,

Actually the checksum calculated for the packet is wrong as per basic summation. The checksum should be c7 ff.

Checksum = (0x01+(0xFFFF- (0x01+0x38)))= FF C7

can you try this?

Thanks,

Hima

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