J722SXH01EVM: J722XH01EVM

Hi Zorah,

In Linux device tree this should be set to output low here: https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/tree/arch/arm64/boot/dts/ti/k3-j722s-evm.dts?h=ti-linux-6.1.y#n430

Is it not setting to low?

Regards,

Takuma

No by default it is set to 1. Let me add you to the email chain describing this problem.

Is there any way to set it to 0 using the syscfg?

Hi Zorah, 

I assume this is not using Linux. I'm not too savvy with how RTOS does the GPIO configuring, so I will reassign this to someone that may be able to help you more. 

In the meantime, I did some digging through and found this GPIO example in the MCU+ SDK: https://software-dl.ti.com/jacinto7/esd/processor-sdk-rtos-j722s/09_02_00_05/exports/docs/mcu_plus_sdk_j722s_09_02_00_41/docs/api_guide_j722s/DRIVERS_GPIO_PAGE.html

And since the particular GPIO wanting to change is on the IO expander, there is an API that is used to initialize and control the output documented here: https://software-dl.ti.com/jacinto7/esd/processor-sdk-rtos-j722s/09_02_00_05/exports/docs/mcu_plus_sdk_j722s_09_02_00_41/docs/api_guide_j722s/group__BOARD__IO__EXPANDER__TCA6416__MODULE.html

Please feel free to look through them and if there is a question, please post back.

Regards,

Takuma

Hi Zorah, 

Zorah Ahmad said:

Is there any way to set it to 0 using the syscfg?

The GPIO is connected in IO Expander ,so we can't use syscfg here

Zorah Ahmad said:

In order to operate the GPIO on J28.37 I need to switch TRC_MUX_SEL to 0. How to I do that? Below pictures are from schematic given here www.ti.com/.../J722SXH01EVM

Please refer the code below to set the gpio of the IO expander. Let us know if this is helpful.

TCA6424_Config config;
    TCA6424_Params param;
    int32_t status;

    param.i2cInstance = I2C_INSTANCE_0;
    param.i2cAddress  = 0x23U;

    status = TCA6424_open(&config, &param);
    if (status != SystemP_SUCCESS)
    {
        return SystemP_FAILURE;
    }
    status = TCA6424_config(&config, 17U, TCA6424_MODE_OUTPUT);
    if (status != SystemP_SUCCESS)
    {
        return SystemP_FAILURE;
    }
    status = TCA6424_setOutput(&config, 17U, TCA6424_OUT_STATE_HIGH);
    if (status != SystemP_SUCCESS)
    {
        return SystemP_FAILURE;
    }
    TCA6424_close(&config);

Regards,

Karthik

Can you please share the full code or where you got it from?

What is I2C_INSTANCE_0? 

In the shared code below

status = TCA6424_config(&config, 17U, TCA6424_MODE_OUTPUT);

Why is pin num 17 used?

Is TRC_MUX_SEL not pin 1?

Hi Zorah,

Source code for RTOS is in the RTOS SDK zip file: https://www.ti.com/tool/download/PROCESSOR-SDK-RTOS-J722S 

I2C_INSTANCE_0 I assume is the I2C bus number. Karthikeyan S, please correct me if I am wrong.

TRC_MUX_SEL should be pin 0. I think the example is just a generic example that just happen to use pin 17.

Regards,

Takuma

When I run the above example after 

status = TCA6424_config(&config, 1U, TCA6424_MODE_OUTPUT);
if (status != SystemP_SUCCESS)

I get status=-12 and no change in gpio pin after enabling gpio indicating the above code is not working

Is any other initialization in terms of i2c needed prior to this other than setting it in syscfg?

Hi Zorah,

Zorah Ahmad said:

Can you please share the full code or where you got it from?

This generic reference code can be used to make GPIO 17 high, we don't have any examples for IO Expander. therefore you can change the gpio J28.37  instead than the gpio 17.

Zorah Ahmad said:

Is any other initialization in terms of i2c needed prior to this other than setting it in syscfg

Yes,you need to enable the I2C_INSTANCE_0 in syscfg.

Regards,

Karthik