st7mc pwm problem

huaer2000 · ‎2004-10-07

Posted on October 08, 2004 at 07:30

st7mc pwm problem

huaer2000 · ‎2011-05-17

Posted on May 17, 2011 at 10:17

I want to control a BLDC(12V,2 pole) in sensorless mode. I have used Kanda Kit for ST72141 to run the motor and success(voltage mode, open loop). Now I want to use ST7MC1K2T6 to run it. I have changed the ST7MC sensorless BLDC libary for ST7MC2N6B6 to adapt ST7MC1K2T6 (I changed the followings: Rom start address from 8000 to E000, Ram from 200 to 100 fro bss section, remove LED operation part code, remove LIN and RS232 part code, reddefine ON/OFF key to PC0). all the setting for ST7MC is from Kanda settings. But the result is motor doesn't run. I have measured the MCO0-5 pin with oscillascope, I found there is no PWM signal output in highside of phase A(MCO0) in prepositioning phase). I think this is very stange. attahced is my source code. I have spend several day on this project. pls note that I use Kanda Kit power stage with my own control board(ST7MC1K2T6, plus ICC connector, MCES pin with pull up resistor, MCCREF with volatage near 5V, MCCFI1 pin connected to GND). Could you do me a favor to tell me why there is no PWM output in MCO0 pin in prepositioning phase?

florent2399 · ‎2011-05-17

Posted on May 17, 2011 at 10:17

First of all, make sure you don't have a hardware problem -> do not change anything from the original library and program the ST7MC1 with your motor settings (for the moment all the chips come with the same die (will change very soon): 60K ROM/2K RAM).

If there's no PWM, check your hardware. If yes, software problem in your modified library.

florent2399 · ‎2011-05-17

Posted on May 17, 2011 at 10:17

For your drivers, you only need to update MPOL register value in the original library (line 382, mtc.c). You need to update the watchdog value accordingly. (MCO output state after reset)

ldefend2 · ‎2011-05-17

Posted on May 17, 2011 at 10:17

1) ST7MC1 has a small RAM, 384 bytes only, are you sure that it is enough?

2) ST7MC1 has a just 8K of FLASH memory, can you fit your project (although shortened) into the MCU?

3) PWM doesn't work on MCO outputs, but I didn't understand... have you programmed the MCU? Have you launched Visual Debug? I suggest you launch a debugging session by using Visual Debug and check step by step where the problem is.

4) Your C library is incomplete. You must add the .h files. You can beget them by using the control panel.

5) Please check the electric connection

Luca Defend

http://www.softecmicro.com

huaer2000 · ‎2011-05-17

Posted on May 17, 2011 at 10:17

yesterday I use AK-ST7FMC starter kit to run my motor, it success. But today

I run the motor again. but I failed. the feedback is motor stalled. I don't know why. Could anyone tell me what can make the motor stalled?

Best regards,

mcuinterest

gaetano · ‎2011-05-17

Posted on May 17, 2011 at 10:17

Hi,

please, might you specify the setting used for Starter Kit and Control Panel (GUI 1.0) and what changes you did after the last successfully run.

Did you use the BLDC motor included in the starter kit or another motor?

Tanio

huaer2000 · ‎2011-05-17

Posted on May 17, 2011 at 10:17

I use another motor: 2poles, BLDC for model.