MSP430 MCU Development Record (5)

tiankai001

MSP430 MCU Development Record (5) [Copy link]

This content is originally created by EEWORLD forum user tiankai001. If you need to reprint or use it for commercial purposes, you must obtain the author's consent and indicate the source MSP430 MCU Development Record (5) Phenomenon: When debugging the msp430f6723 microcontroller, there is always a problem of large static current (about 100uA larger than the normal value). After checking the program and circuit, no problem was found. Test: Confirm that there is no problem with the program and circuit. So I adopted a more stupid method, first shielding all the programs, initializing the ports according to the correct state, and then restoring a part of the program each time, observing the current after adding a part of the program, and finally found that the current abnormality occurred during the AD conversion part. Check the AD conversion circuit, port configuration, program, and register configuration, and no problem was found. Try to turn off the AD conversion program and find that the current is still abnormal. At this time, the port is configured as a normal I/O port and the port direction is input. Simply set the port to output high level and find that the current is normal. It is normal to set it to output low level current. As long as the port is set to input port, the current is abnormal. (Port is P1.0) Because this port is the AD conversion channel, it cannot be used as a normal I/O port. Looking at the port function of MSP430F6723 microcontroller, it is found that P9 port also has some AD conversion channels, so the AD conversion channel of P1 port is replaced with the AD conversion channel of P9 port, and the AD channel of P1 port is set to a normal I/O port, the direction is output, and the current is normal. Verification: The reason is found. The two AD conversion channels corresponding to the two ports P1.0 and P1.1 cannot be used. Once used, abnormal current will occur. (I have tried to set these two AD channels to normal I/O and output direction, and then switch to AD function and input direction when using them. However, it takes a long time to collect stable and accurate voltage after switching. The extended time leads to increased power consumption, so this solution is not an option.) Remarks: I asked TI's customer service about this problem, but they couldn't explain it clearly. After checking all the relevant manuals, there was no such explanation. It may also be my mistake, but the current situation is that after changing to the AD channel of P9 port, everything is normal. So I think it is a defect of this microcontroller.

alan000345

Good post, thanks for sharing.

tiankai001

alan000345 posted on 2018-12-14 16:23 Good post, thank you for sharing.

Thank you