uart 1 problem

Yolanda Zhong

Other Parts Discussed in Thread: DA8XX

hey,

i use OMAP L138 ( EVM) . As you know, OMAP L 138 has three uarts. It use the uart 2 to connect with console window. i have some questions related to other two uarts

1) could i enable either uart 0 or uart 1 to talk with my external device ?

2), i enabled uart 1 by open("/dev/ttyS1", O_RDWR | O_NONBLOCK | O_NOCTTY);

and i tried to send the data through the uart. //write(fd, &data, DATALEN);

but, i did not see any signal at tx port. it seems that uart 1 is not setup.

here is serial info.

serinfo:1.0 driver revision:
0: uart:16550A mmio:0x01C42000 irq:25 tx:0 rx:0 CTS
1: uart:16550A mmio:0x01D0C000 irq:53 tx:20 rx:0
2: uart:16550A mmio:0x01D0D000 irq:61 tx:2547 rx:194 RTS|DTR

One thing that I did was to enable to UART1 in the kernel by removing the lines shutting down UART1 (in board-da850-evm.c):

// __raw_writel(0, IO_ADDRESS(DA8XX_UART1_BASE) + 0x30);

__raw_writel(0xFFFF6FFF, IO_ADDRESS(DA8XX_UART1_BASE) + 0x30);

Any suggestions on the problems?

thanks!

Yolanda

over 15 years ago

0 jc-ti over 15 years ago

TI__Mastermind 27585 points

Where are you probing the TX signal? On the EVM the RS232 header is connected to UART2 pins only, so you cannot use that header with UART0/1.

Jeff

0 Yolanda Zhong over 15 years ago in reply to jc-ti

Prodigy 200 points

Jeffs,

i probed the UAR1 TX signal (pin 10) at J30 connection ( audio expenasion board).

Yolanda

0 Brad Griffis over 15 years ago in reply to Yolanda Zhong

TI__Guru*** 125430 points

The driver may already be handling this, but it would be good to verify that the PINMUX registers are being configured correctly and that the UART has been enabled through the PSC. Both of these items are discussed in the System Reference Guide.

0 Yolanda Zhong over 15 years ago in reply to Brad Griffis

Prodigy 200 points

i checked PINMUX4 register for ( uart 1 tx and uart 1 rx). it show 0x222288. It seems that the pinmux register are not configured correctly for uart 1. do you know why that is happened? and what should i do to fix this problem?

thanks!

0 Brad Griffis over 15 years ago in reply to Yolanda Zhong

TI__Guru*** 125430 points

As a quick test, can you just change the PINMUX value with the emulator. You might need to start a new thread in the Linux forum to get more info on how this should be configured in Linux. It's not clear to me if there is a bug in the driver or if something is not configured properly elsewhere.

0 Carl Heyendal over 15 years ago in reply to Brad Griffis

Prodigy 210 points

I'm having the same problem. Did anyone arrive at a solution for this problem?

thanx

/carl h.

0 jc-ti over 15 years ago in reply to Carl Heyendal

TI__Mastermind 27585 points

Which problem are you having? Is the pinmux not set correctly for UART1?

Jeff

0 Carl Heyendal over 15 years ago in reply to jc-ti

Prodigy 210 points

The Uart1 problem in the first post.

I'm a newbie to these processors and developement environment. I knew nothing of the pinnux utility so I investigated and found out what it does. Seems like a handy utility to start from scatch with, but I have no idea what my current pin mux configuration is. How can I avoid breaking my current pin mux configuration? Can I import the current header file, make a change to enable Uart1, and then save a new header file? Where does it exist in Linux? Does Linux have to be re-compiled? Or am I missing a concept here?

thanx

/carl

0 jc-ti over 15 years ago in reply to Carl Heyendal

TI__Mastermind 27585 points

Check out the System Reference Guide for the addresses and descriptions of the pinmux registers. You will need CCS and an emulator to connect to the ARM to check this. If UART1 is not enabled then you will want to repost this question in the Linux sub-forum.

Jeff

0 Carl Heyendal over 15 years ago in reply to jc-ti

Prodigy 210 points

I'm sure the Linux forum will tell me to use the pinmux utility to enable the pins used for uart1, generate a new header, and then re-compile. But I'll do it anyways I guess.

/carl h.

0 Carl Heyendal over 15 years ago in reply to Carl Heyendal

Prodigy 210 points

But before I do that, does anyone know the name of the pinmux header file and where it exists?

/carl h

0 clam over 15 years ago in reply to Carl Heyendal

TI__Expert 8785 points

You'll want to download the Linux DSK, http://software-dl.ti.com/dsps/dsps_public_sw/psp/LinuxPSP/DaVinci_03_20/index.html. The pinmux file should be located at [install directory] / src / u-boot / uboot-[version] / board / davinci / da8xxevm / da850evm.c.

If you have additional questions about Linux, you should post in the Linux forum. They have more expertise on how to compile and modify the u-boot.

--Christina

0 Gary Wu over 13 years ago in reply to clam

TI__Expert 3313 points

You should check the files below.

Arch\arm\mach-davinci\include\mach\mux.h

enum davinci_da850_index{}

arch\arm\mach-davinci\da850.c

static const struct mux_config da850_pins[]

And this file is also needed to check.

Arch/arm/arhc-davinci/board-da850-evm.c

/* Support for UART 1 */

ret = da8xx_pinmux_setup(da850_uart1_pins);

if (ret)

pr_warning("da850_evm_init: UART 1 mux setup failed:"

Processors

Processors forum

uart 1 problem