LP-AM243: Trouble with reading GPIO

Justin Reina

Part Number: LP-AM243
Other Parts Discussed in Thread: AM2434, , SYSCONFIG

Hi,

I am new to the AM2434 and trying to get a GPIO read demo running on my LP-AM243 -

Demo Attempt:

//Using J4.10 - GPIO1_2 (BP.31)

//Pin Def
uint32_t gpioBaseAddr = (uint32_t) AddrTranslateP_getLocalAddr(CSL_GPIO1_BASE);
uint32_t pinNum       = 2;

//Setup
GPIO_setDirMode(gpioBaseAddr, pinNum, GPIO_DIRECTION_INPUT);

//Read
uint32_t val = GPIO_pinRead(gpioBaseAddr, pinNum);

This is not working, I always get '0' for val when I apply 0V or 3.3V.

How do I get the GPIO Read routine to work?

over 3 years ago

+1 Frank Livingston over 3 years ago

TI__Mastermind 29338 points

Hi Justin,

If you are new to AM243x, I suggest starting with the AM243x MCU+ Academy: https://dev.ti.com/tirex/explore/node?node=AFE2McpKgDFYraxZMF08-A__6zyEKJF__LATEST

Next, read through these sections of the MCU+SDK docs:

It looks like you aren't using Sysconfig to configure the GPIO. I suggest reviewing this example: https://software-dl.ti.com/mcu-plus-sdk/esd/AM243X/08_02_00_31/exports/docs/api_guide_am243x/EXAMPLES_DRIVERS_GPIO_INPUT_INTERRUPT.html

Import the CCS project, double-click on example.syscfg in the imported project, and then select "GPIO" to review the options selected for the GPIO_PUSH_BUTTON.

Follow the steps below to update the example to only read the GPIO. The value from the User Push Button on the LP will be displayed to the UART.

Regards,
Frank

example.syscfg: In settings for GPIO_PUSH_BUTTON, set "Trigger Type" to "None".

gpio_input_interrupt.c: change body of gpio_input_interrupt_main() to the following:

            /* Open drivers to open the UART driver for console */
            Drivers_open();
            Board_driversOpen();

            DebugP_log("GPIO Input Test Started ...\r\n");

            pinNum          = GPIO_PUSH_BUTTON_PIN;

            /* Address translate */
            gGpioBaseAddr = (uint32_t) AddrTranslateP_getLocalAddr(gGpioBaseAddr);

            /* Setup GPIO for interrupt generation */
            GPIO_setDirMode(gGpioBaseAddr, pinNum, GPIO_PUSH_BUTTON_DIR);

            while (1)
            {
                gpioVal = GPIO_pinRead(gGpioBaseAddr, pinNum);
                DebugP_log("GPIO value = %d\r\n", gpioVal);
            }

0 Justin Reina over 3 years ago in reply to Frank Livingston

Prodigy 91 points

it works!! Thank you!!!

See attached for ref, thank you Frank you made this very easy

soln - gpio_input_interrupt_am243x-lp_r5fss0-0_nortos_ti-arm-clang (2).zip

0 Frank Livingston over 3 years ago in reply to Justin Reina

TI__Mastermind 29338 points

Justin,

No problem, I'm glad to hear it's working for you! Thanks also for sharing the final solution.

Regards,
Frank

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LP-AM243: Trouble with reading GPIO