topic Re: i.mx25 pdk and ov2640 cmos sensor in i.MX Processors

i.mx25 pdk and ov2640 cmos sensor

garytee — Fri, 24 May 2013 16:23:39 GMT

Has anyone in this community used the ov2640 cmos sensor on the imx25-3stack board?

I have the i.mx25 pdk 3-stack development kit and I'm using L2.6.31_09.12.00_sdk_source. I'm trying to run /unit_tests/csi_v4l2_capture.out and /unit_tests/csi_v4l2_overlay.out. These test applications fail with the following message: >>i2c-adapter i2c-0: ACK not received<<.

I have verified that the dip switches on the personality board are set for i2c1 and I'm not enabling 'sim' on the boot command line.

Thank you for your time.

Re: i.mx25 pdk and ov2640 cmos sensor

chrisruehl — Wed, 29 May 2013 04:22:26 GMT

Hi Garytee,

I haven't a imx25 but fight with i2c with our new development.

I found the tool

i2cdetect -y 0

0 1 2 3 4 5 6 7 8 9 a b c d e f

00: -- -- -- -- -- -- -- -- -- -- -- -- --

10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

30: UU -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

70: -- -- -- -- -- -- -- --

very helpful to see if the ov2640 is responding on the i2c bus

(in my case on address 0x30)

I remember some people change/add pull-downs to the i2c bus to stabilize it.

cheers

Chris

Re: i.mx25 pdk and ov2640 cmos sensor

garytee — Wed, 29 May 2013 06:10:16 GMT

Chris,

Thank you very much for your reply. I will try i2cdetect -y 0 and let you know what I discover. Thank you for your reminder on increasing the I2C pull ups. I believe the hardware engineer had to change those on our client's board which is based on the 3-stack design.

Best Regards,

Gary

Re: i.mx25 pdk and ov2640 cmos sensor

chrisruehl — Wed, 29 May 2013 06:28:15 GMT

Gary,

yeah I2C is very sensitive. Good luck with it.

Chris

Re: i.mx25 pdk and ov2640 cmos sensor

YixingKong — Fri, 14 Jun 2013 05:17:25 GMT

Gary, if Chris's comment helps you, please click Correct Answer/Helpful answer.

Thanks,

Yixing