STM32 Encoder Mode vs Remap CH1, CH2 vs Index Mode

[mcagriaksoy]

Hi,

I am using two rotary encoders on an STM32U5G9ZJT.

Currently I have:
- TIM8_CH1 and CH2 available
- TIM3_CH3 and CH4 available

I know that standard encoder mode uses CH1 and CH2.

CubeMX shows options like:
- Encoder Mode (with remap CH1/CH2)
- Encoder Mode + Index (with remap CH1/CH2 + ETR)

My encoders are simple mechanical rotary encoders.

Question:
Should I use "Encoder Mode with remap" to map CH3/CH4 to CH1/CH2,
or is there any benefit to using "Encoder Mode + Index"?

Is there any difference, If I use "TIM8 in encoder mode" or "TIM3 encoder mode from remap"

Thanks!

[waclawek.jan]

There's no point using the "Encoder+Index" mode if you don't have an encoder with an index output.

You cannot use TIMx_CH3/CH4 for Encoder. Fullstop.

JW