Hello,
I am in the process of developing for updates of a MSP430 from a host processor (an iMX, but that's not relevant).
Using the GPIO on the iMX, I attempt to put the MSP430 into bootloader mode using the RST/TST sequence. I then proceed to send the RX-password command along with the password, derived from the first 16 words of the vector table, as specified. I receive no response, from which I can only infer that the password is incorrect (the datasheet for this variant states that no response is expected for an incorrect password). I ahve checked the CRC and it appears correct (would it have bee ACKed with a 0x52 response in thet case?).
The 16 words (in little-endian) in the vector table are:
@FFE0
30 EE 0A F0 0A F0 0A F0 0A F0 0A F0 0A F0 C0 EF
90 EF 0A F0 90 ED 0A F0 0A F0 0A F0 0A F0 BA EC
q
We have also tried reversing the endianness, for completeness, to no avail.
The get-password messages was as follows.
0x80, 0x21, 0x00, 0x11, 0x9E, 0xED, 0x78, 0xEF,
0x78, 0xEF, 0x78, 0xEF, 0x78, 0xEF, 0x78, 0xEF,
0x78, 0xEF, 0x2E, 0xEF, 0xFE, 0xEE, 0x78, 0xEF,
0xFE, 0xEC, 0x78, 0xEF, 0x78, 0xEF, 0x78, 0xEF,
0x78, 0xEF, 0x28, 0xEC, 0xA1, 0x28
The waveform is as shown here. Note that here, RX is the data received by the MSP430.
No response is received, as can be seen.
Significantly, there is data being sent from the host following the BSL invocation, but the RX line is not changing. The host has been checked, and it is not holding the line high. If the BSL invocation is omitted, the line is free to move and data is visible. To all appearance, the RX line is being held high by the MSP430.
One observation was that if the BSL invocation didn't occur, but a valid message was sent to the BSL, a response is received, albeit before the message is completed. I doubt this has any relevance, but it is curious. The response looks like a valid ACK (header incorrect).
We have exhausted all avenues for this puzzle.
Can anyone help?
Thanks
Graham