issue with GPIO_126 line configuration

Hi ,

I am using OMAP3530 processor 's MMC1 interface to communicate to our wifi-SDIO card. We are facing a problem while configuring the OMAP3530's GPIO 126 (MMC1_DAT4). The default state of this GPIO pin is "Logic low" but we were trying to make it "Logic high" by changing the following registers,

1) CONTROL_PADCONF_MMC1_DAT4 (0x011c) : To configuring line as GPIO input line with pulling up.
2) CONTROL_PBIAS_LITE ( set (3.0V) and reset(1.8V) <-- PBIASLITEVMODE1) : Tried with both setting and resetting the bit PBIASLITEVMODE1, but we were getting logic low at GPIO126. Please let us know what we suppose to do, to get logic high at GPIO126?

Thanks in advance,


We had the same issue on the -xM. We could never get it to work when using the pins assigned to the MMC block of pins as GPIO so I had to move it to another location. It may be possible to make it work, but I was not able to make it work.


Hi Gerald,
          I am able to make GPIO line as "Logic High". You need to make some extra configurations in order to work. Following is the configuration.
1. Set DEV_GRP to 0x1 in the VSIM_DEV_GRP Register.
2. Set VSEL to 0x7 in the VSIM_DEDICATED Register.

This configuration will drive the 3.0V/1.8V to the MMC4-MMC7 lines.

Ravi Holal

Gerald Coley wrote:

Awesome! Glad you figured it out! I wll definitley make a note of it.