Help my PWM
Question about PWM output:
I am using BX24s PWM (pin26) to control a 24V DC motor with a driver LMD18200, and it has no problem at all. However, suddenly, the PWM doesnt work, while other function is fine. Also I have checked by using the dual PWM problem provided, the following cases can be observed.
Firstly, I have 2 BX24 (may called BX24-a and BX24-b) and those both pin26, 27 dont work now.
Pin26 always output a constant voltage about 3.5V. Even I program it to be low, PutPin (26 , 0), It also output 3.5V.
Pin27 is able to output PWM but with low frequency (rate-setting is 5, and use 8-bit mode). If higher frequency, 14 kHz, is set, the waveform look like a capacitors charging and discharging curve, and wont reach 0V.
Pin26 can output PWM with low frequency, but it wont reach 0V such that the single is triggered between 5V and 3.5V. For high frequency, the waveform look like a capacitors charging and discharging curve.
Pin27 is the same as Pin26 (BX24-b).
Is my BX24 broken? or any other reason. I have tried to program Timer2 to output PWM, it works well. But now I dare not to use Time2 in my project before the above question solved. Please tell me the answer.
YM - uT
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