1、We are currently developing PLC,we need EQEP drivers,please help me resolve it .
2、SDK9.0 has been ported,but Touch screen(LVDS) cannot be touched and controlled,please help me resolve it.E:\c381461c41e435d1942d45edd59d321f.mp4
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1、We are currently developing PLC,we need EQEP drivers,please help me resolve it .
2、SDK9.0 has been ported,but Touch screen(LVDS) cannot be touched and controlled,please help me resolve it.E:\c381461c41e435d1942d45edd59d321f.mp4
Hello tansai,
EQEP is not supported in AM62x Linux SDK 9.0 and earlier SDK releases. However, if you provide me with more details about the feature set needed in your EQEP usecase, I can add it to the requirement to add EQEP support at some point in the future.
I am not able to see the mp4 file that you attached. Please provide additional details about your touchscreen setup (e.g., is this touchscreen controlled over I2C or a different interface? include any changes you made to the Linux devicetree. Describe the behavior you are observing in more detail).
Regards,
Nick
1、The EQEP module includes the following features: • Input synchronization • Three stage/six stage digital noise filter • Quadrature decoder unit • Position counter and control unit for position measurement • Quadrature edge capture unit for low-speed measurement • Unit time base for speed and frequency measurement • Watchdog timer for detecting stalls • EQEP inputs (A/B/INDEX and STROBE) are available at chip level • EQEP phase error output is also available. The status of the phase error can be observed by software through the register in the CTRL_MMR0 module.• Counting modes: – Quadrature – Clockwise / Counter Clockwise – Count / Direction • Start of Convert input for on-chip Strobe • EQEP internal strobe (EQEP Strobe input is logically ORed with EQEP A and B inputs) may be used to: – Initialize the Position Counter with a non-zero value (for example, due to a limit switch input becoming active) – Snapshot the Position Counter into the register – Gate the EQEP Index input preventing it from resetting the Position Counter。now pulse input is 400kHz
2、This touchscreen is controlled over I2C,if I touch any icon,it is no response.
Hello tansai,
EQEP feature set needed
It looks like you just copy-pasted the technical reference manual (TRM) chapter's feature list of EQEP. That is not helpful for me or the software developers.
Our processors have many, many more hardware features than we could ever implement in software. The Linux developers are NOT going to implement every single EQEP feature that the hardware has.
Please help me understand exactly which features matter in your usecase, so we can ask them to implement the features that actually matter to you.
Touchscreen
1) Are you using a TI EVM or a custom board?
2) Is the touchscreen a TI product? If so, which product?
3) Please attach your devicetree where you define the touchscreen
4) Please show your terminal output that tells us whether Linux tries to connect to the touchscreen
Regards,
Nick
Hello tansai,
EQEP
Does the existing Linux driver for AM335x EQEP have the functions that you need?
https://github.com/torvalds/linux/blob/master/drivers/counter/ti-eqep.c
Looks like you can find some usage notes here:
http://yhbt.net/lore/all/20190802092727.GB30522@icarus/t/
https://lore.kernel.org/all/20211204163409.2a4fd5c5@jic23-huawei/t/
Touchscreen
I cannot perform a schematic review here. Please attach your Linux devicetree definition of the touchscreen, and show us your terminal output where Linux starts up the touchscreen driver.
If you are having trouble getting code working on your custom hardware, I always suggest starting from a "known good" state first. For hardware, your "known good" state is the AM62-SK EVM, connected to this display board: https://www.ti.com/tool/SK-LCD1
Your "known good" software to use with that display board & touchscreen is arch/arm64/boot/dts/ti/k3-am62-lp-sk-microtips-mf101hie-panel.dtso
Regards,
Nick