Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A20 => Topic started by: dennis_k85 on October 30, 2014, 06:50:33 PM

Title: Olimex Lime A10 board corrupts SD card
Post by: dennis_k85 on October 30, 2014, 06:50:33 PM
I am running a Debian A10 image on an Olimex Lime A10 board from a 16 gig micro SD card. It boots and runs fine, but if I try to add or update package it corrupts the SD card. Am I doing something wrong or is there something I need to do before adding packages.

Dennis
Title: Re: Olimex Lime A10 board corrupts SD card
Post by: MBR on November 02, 2014, 09:12:59 AM
No, there is nothing special to be done, if your card gets corrupted when you write on it, there is probably some hardware problem with the SD card or the A10 itself. Try creating a big file (with someting like dd if=/dev/zero of=testfile bs=1024 count=1048576, this will create a 1GB file of zeroes) and watch kernel error messages (with dmesg).
Title: Re: Olimex Lime A10 board corrupts SD card
Post by: JohnS on November 02, 2014, 04:31:47 PM
Could be bad RAM timings / too fast CPU freq.

John
Title: Re: Olimex Lime A10 board corrupts SD card
Post by: dennis_k85 on November 03, 2014, 02:28:07 PM
How do I reduce the clock Frequency?

Dennis
Title: Re: Olimex Lime A10 board corrupts SD card
Post by: progmetalbg on November 03, 2014, 05:11:17 PM
https://wiki.debian.org/HowTo/CpuFrequencyScaling (https://wiki.debian.org/HowTo/CpuFrequencyScaling)
http://www.thinkwiki.org/wiki/How_to_use_cpufrequtils (http://www.thinkwiki.org/wiki/How_to_use_cpufrequtils)

Should be something like:

cpufreq-set -u 900Mhz

where 900 MHz is the new desired max speed of CPU
Title: Re: Olimex Lime A10 board corrupts SD card
Post by: dennis_k85 on November 03, 2014, 07:11:31 PM
Setting the clock frequency to 900Mhz seems to have fixed my issue. I will keep testing.

Dennis
Title: Re: Olimex Lime A10 board corrupts SD card
Post by: dennis_k85 on November 04, 2014, 05:32:22 PM
Even at 900Mhz I am still getting SD card corruption . Any other Ideas?

Dennis
Title: Re: Olimex Lime A10 board corrupts SD card
Post by: progmetalbg on November 04, 2014, 08:03:47 PM
It could be caused by unstable memory. By default DRAM of A10 LIME is clocked at 480 MHz
https://github.com/linux-sunxi/u-boot-sunxi/blob/sunxi/board/sunxi/dram_a10_olinuxino_lime.c (https://github.com/linux-sunxi/u-boot-sunxi/blob/sunxi/board/sunxi/dram_a10_olinuxino_lime.c)
Cubieboard is similar board to A10-OLinuXino-LIME with same SoC Allwinner A10 and its memory is also clocked at 480 MHz. Many people with Cubieboard complain about crashing application during high load and main cause seems to be unstable memory settings.
Memory is initialized in u-boot so it is hard to change settings - you should recompile u-boot for your board and replace the original one on the uSD card. Follow the u-boot part of official A10-OLinuXino-LIME guide, replace 480 with 384 (which should be safe) in board/sunxi/dram_a10_olinuxino_lime.c and compile new u-boot.
https://drive.google.com/file/d/0B-bAEPML8fwla21JNU12RnYxZmM/edit (https://drive.google.com/file/d/0B-bAEPML8fwla21JNU12RnYxZmM/edit)
You can also try different power supply.
If none of this helps your board might be faulty.