DM3730: configuration of GPIO120-129

Sergey Matyukevich

Other Parts Discussed in Thread: DM3730

Hi,

I have a question about configuration of GPIO120,121,126,127 on DM3730. According to DM37xx documentation I have to configure PBIAS cells before using those GPIOs. I am doing the following configuration steps:

1. HW setup

VDDS_X voltage rail is powered to 1V8, VDDS_MMC1 voltage rail is powered to 1V8

2. SW configuration (pseudocode)

I am configuring PBIAS0 cell for GPIO120,121:

CONTROL.CONTROL_PBIAS_LITE &= ~PBIASLITEPWRDNZ0;

CONTROL.CONTROL_PBIAS_LITE &= ~PBIASLITEVMODE0;

msleep(100);

CONTROL.CONTROL_PBIAS_LITE |= PBIASLITEPWRDNZ0;

Then I am doing similar configuration for PBIAS1 cell. It it almost the same: there is just one additional step for GPIO_IO_PWRDNZ bit in CONTROL_WKUP_CTRL register:

CONTROL.CONTROL_WKUP_CTRL &= ~GPIO_IO_PWRDNZ;

CONTROL.CONTROL_PBIAS_LITE &= ~PBIASLITEPWRDNZ1;

CONTROL.CONTROL_PBIAS_LITE &= ~PBIASLITEVMODE1;

msleep(100);

CONTROL.CONTROL_WKUP_CTRL |= GPIO_IO_PWRDNZ;

CONTROL.CONTROL_PBIAS_LITE |= PBIASLITEPWRDNZ1;

As a result I have working GPIO120,121, but I don't get any output on GPIO126,127.

Do I miss something ?

Thanks,

Sergey

over 13 years ago

0 Sergey Matyukevich over 13 years ago

Intellectual 340 points

Update: everything works fine.

Described procedure is correct including both h/w and s/w parts. I used an erroneous value for CONTROL.CONTROL_WKUP_CTRL register. However the steps with manipulating GPIO_IO_PWRDNZ bit are crucial for GPIO12[679] configuration.

Thanks,

Sergey

0 Huai Hellen over 13 years ago in reply to Sergey Matyukevich

Expert 1030 points

Sergey_,

_{Now, I do the same work for gpio12[679], according to your steps, but it still does not work. you say you used an erroneous value for control.control_wkup_ctrl,}

_{then could you pls kindly tell me what the correct value is? Thank you!}

0 Sergey Matyukevich over 13 years ago in reply to Huai Hellen

Intellectual 340 points

Hello,

According to Rev.F of AM/DM37xx TRM, physical address of CONTROL_WKUP_CTRL register is 0x48002A5C. By the way, this document is freely available from TI portal: http://www.ti.com/product/dm3730.

Thanks,

Sergey

0 Huai Hellen over 13 years ago in reply to Huai Hellen

Expert 1030 points

Yes, I use the right value of control_wkup_ctr physical address, but it could not work yet.

could you tell me whether there are some considerations I missed?

0 Sergey Matyukevich over 13 years ago in reply to Huai Hellen

Intellectual 340 points

Hello,

Take a look at the first message of this thread: it is message with configuration steps for those GPIOs. Besides, for additional h/w details take a look at the following article on omap wiki: http://processors.wiki.ti.com/index.php?title=Additional_Configuration_for_GPIO120-129_on_OMAP35x

Thanks,

Sergey

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DM3730: configuration of GPIO120-129