AnsweredAssumed Answered

How to set CANSTBY gpio low on IMX6Q-sabre-sdp

Question asked by Jiawei Yu on Dec 23, 2015
Latest reply on Dec 23, 2015 by igorpadykov

Hello,

 

I am using CAN on IMX6Q-sabre-sdp with Freescale BSP r14.10.28.

 

I modified flexcan settings(status = "okay";) in imx6qdl.dtsi and set ethernet "fec"  status to "disable" due to pin conflict.

 

Besides I include the driver for Freecsale Flexcan in kernel menconfig. Then I make dtb and zImage file again.

 

After copy the new zImage and sabresd.sdb files to the board, I use cmd "ip link set can0 up type can bitrate 250000" to enable CAN. “ifconfig -a” cmd shows that CAN0 is up and running properly.However, I can't receive any message using the cmd "cansend can0 111#1122334455667788" with a CAN analyser.

 

It seems that the cause is the canstandby gpio status is high. The TJA1040 datasheet indicates the stby pin status must be low.I tried to force the pin to low with a cable connect to GND and it works. Thus I think it is key to set the canstby pin to low to solve the problem.

 

How can i set the canstby gpio(GPIO4_IO5,GPIO19) to low status?

1.jpg

 

Much thanks!

Outcomes