Hi all,
I'm trying to spin a 3-phase BLDC using an MSP430-F5529 and a DRV8320S without using TI's InstaSPIN GUI. A colleague of mine pointed me to the the “TMS320x2802x, 2803x Piccolo Enhanced Pulse Width Modulator (ePWM) Module Reference Guide” (Literature Number: SPRUGE9E) and I came across the waveform example on page 90. I know that the TMS320x2802x is used in the DRV8312-C2-KIT which also uses half-H bridges to spin motors so I figured I could simply replicate the wave from on the MSP430-F5529 using table 3 on page 9 of the “BOOSTXL-DRV8320x EVM User’s Guide” to apply PWM signals to the pins corresponding to the high and low side switches of each phase. When I thought I had my code all set up, I ran it supplying about 40 volts and the motor turned and stayed put in a fixed position.
I connected oscilloscope probes to the high and low switches of each phase and saw that I was controlling the high sides as expected, but when I adjusted the duty cycle of the low sides the board was actually adjusting the high side signals as well even though I was changing values in different capture and compare registers. I wanted to make sure my program didn't damage the board so I tried running the InstaSPIN GUI and the motor started to turn, immediately stopped, threw a voltage error flag, cleared the flag, and repeated the process again and again. I made sure that InstaSPIN was working before I started writing my code , but after running my program I can no longer get the motor to spin with the GUI.
Does this behavior grantee that I damaged the hardware when trying my code, or does the funky high and low switch behavior indicate that something else is at play?
Ill try to provide any other information you may need if I haven't given enough to answer those questions.
-Fernando
