TM4C123GH6PM: Required more no. of QEI for my project

Hello Yashwanth,

There really isn't a clean way to do that. In theory I suppose you could multiplex the QEI signals if you can get away with cycling between motors.

I would instead recommend you use the PWM module for controlling that many motors.

Hi Ralph Jacobi,

Thank you for quick response.

I'm comfortable with using of PWM to control motors.

I want to get the postion,velocity and directions for some of my project modules.
My problem is to get additional 6 more QEI s .

Regards,
Yashwanth Kumar Gandeti.

In the past we've used QEI ICs that communicate via SPI. They weren't from TI; I don't know whether TI offers such parts. Those ICs provided position counting only. They did not provide velocity measurement but that can be calculated by taking the delta between two (or more) consecutive reads. Since the ICs did not handle the "index" pulse of the QEI, we would input that into an interrupt-capable GPIO.

 all 8 modules (4 modules were QEI)

Hi Ralphi,

Can you explain what you exactly meant by 4 modules were QEI?
(I want to use 8 moudule of QEI).

Regards,

Yashwanth Kumar Gandeti

Hello Yashwanth,

Sorry typographical error. 4 modules PER each QEI. I edited my post for proper clarity.

Hi twelve12pm,
Do you remember model No. of QEI ICs you used ?
Regards,
Yashwanth.

LSI/CSI part number LS7366R.

Hi Twelve12pm,

Thanks a lot for sharing Chip No.
So, according to my requirement I should use 6 chips of this model is it?

Regards,

Yashwanth Kumar Gandeti

Yashwanth Gandeti said:

Hi Twelve12pm,

Thanks a lot for sharing Chip No.
So, according to my requirement I should use 6 chips of this model is it?

Regards,

Yashwanth Kumar Gandeti

Each LS7366R provides one QEI, so yes, if you use that and you need 6 QEIs, you would need 6 ICs. It would probably be better for board space, BOM count, etc., if you could find a chip with more QEIs in one IC. If you do find one, please let us know!