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OLinuXino Android / Linux boards and System On Modules => A13 => Topic started by: sandro on January 17, 2013, 11:24:38 AM

Title: problem with Mod-RS485-ISO on UETX
Post by: sandro on January 17, 2013, 11:24:38 AM
Hi at all.
I have a A13 rev C.
I use script_GPIO_LCD_800x480.
At start, maybe because in UART1 i have teh bootloader, the system don't start if I have the Mod-RS485-ISO connect on UETX.
What can I do?

Thanks
Sandro
Title: Re: problem with Mod-RS485-ISO on UETX
Post by: jwischka on January 17, 2013, 04:05:20 PM
Have you tried rebuilding u-boot with a different UART?
Title: Re: problem with Mod-RS485-ISO on UETX
Post by: sandro on January 17, 2013, 05:22:12 PM
yes but don't work for me.
I have only 2 uart (0 and 1).
I need the UART1, but the UART0 in A13 rev C is shared with the SD.
If I uncomment  #define CONFIG_UART0_PORT_F in sun5i.h


/* Define this to have serial channel 1 (UART0) redirected to SD port */
/* #define CONFIG_UART0_PORT_F */

#ifndef CONFIG_CONS_INDEX
#ifdef CONFIG_UART0_PORT_F
#define CONFIG_CONS_INDEX         1         /* UART0 on PORT_F (sdcard) */
#else
#define CONFIG_CONS_INDEX         2         /* UART1 */
#endif
#endif


System don't start too.

Thanks
Title: Re: problem with Mod-RS485-ISO on UETX
Post by: vinifr on January 18, 2013, 12:09:06 PM
If you have a VGA LCD you can changed console from /dev/ttyS0 to /dev/tty[1-6].
Enable /dev/tty[1-6] and disable /dev/ttyS0 in /etc/inittab
Code Select

1:2345:respawn:/sbin/getty 38400 tty1
2:23:respawn:/sbin/getty 38400 tty2
3:23:respawn:/sbin/getty 38400 tty3
4:23:respawn:/sbin/getty 38400 tty4
5:23:respawn:/sbin/getty 38400 tty5
6:23:respawn:/sbin/getty 38400 tty6

#T0:2345:respawn:/sbin/getty -L ttyS0 115200 linux


Code Select

setenv bootargs console=/dev/tty1 root=/dev/mmcblk0p2 rootwait panic=10 ${extra}
fatload mmc 0 0x43000000 script.bin
fatload mmc 0 0x48000000 uImage
bootm 0x48000000
Title: Re: problem with Mod-RS485-ISO on UETX
Post by: sandro on January 21, 2013, 06:57:37 PM
The problem it's on the login or on the kernel messagges, but on the bootloader.
With the Mod-RS485-ISO the bootloader seem like I press the ctrl-c at start.
I tried to recompile the bootloader too (with silent option) but it doesn't work.
I tried to give the feed at Mod-RS485-ISO with a gpio, so it's 0V at the start, but it doesn't work too.

Thanks
Title: Re: problem with Mod-RS485-ISO on UETX
Post by: JohnS on January 21, 2013, 07:33:36 PM
Can you get a log of the messages on uart1?  (Such as by using screen or putty)

I'm not clear how far it gets before going wrong.

I don't think u-boot cares about what is on uart0 but let's see the log :)

I do it on linux using:
screen -L /dev/ttyUSB0 115200

and it writes screenlog.0 for example
Title: Re: problem with Mod-RS485-ISO on UETX
Post by: sandro on January 22, 2013, 04:27:12 PM
I can't access to Linux.
If I start the system with Mod-RS485-ISO on UETX the system remains with black screen
If without restart the system, I connect on the UART1 a serial, I see that the system is stopped here:

Unknown command 'U-Boot' - try 'help'
sun5i#

then on the bootloader
Title: Re: problem with Mod-RS485-ISO on UETX
Post by: JohnS on January 22, 2013, 05:15:36 PM
What was before that?  We need all of it from when you press Reset
Title: Re: problem with Mod-RS485-ISO on UETX
Post by: sandro on January 23, 2013, 03:19:51 PM
I connect the MOD-rs485-iso on the uext. I feed the board. I wait it start but it don't start.
If now I connect a rs232 interface on the UART1 I can see the bootloader prompt.
Title: Re: problem with Mod-RS485-ISO on UETX
Post by: JohnS on January 23, 2013, 04:20:20 PM
Yes but what was on the uart BEFORE what you posted?  All the stuff from when you reset the board.  I don't see any way to help you without the data.  Do not press any keys to interrupt the board's attempt to boot.
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