topic Re: [IMX8] ISI errors in i.MX Processors

[IMX8] ISI errors

khaledbalbaa — Sun, 01 Nov 2020 09:57:50 GMT

We have noticed an error interrupt called OFLW_EARLY_VSYNC_ERR , this interrupt is fired on every video capture start/stop calling for only 1 time and after that the interrupt disappear

Question:

1. What is this interrupt stands for? (what error does it notify for)

2. What could be the cause for this error to pop up? and why does it only pop up in the start or stop?

Re: [IMX8] ISI errors

joanxie — Thu, 05 Nov 2020 07:46:57 GMT

are you sure the error message is OFLW_EARLY_VSYNC_ERR? if yes, pls send the whole log file to me, I coudln' t

Re: [IMX8] ISI errors

khaledbalbaa — Thu, 05 Nov 2020 10:48:20 GMT

Hello joanxie,

Please find below the UART log, you will find it at line 258

[Thu Nov 05 12:24:52.058 2020] IRQ IMX_ISI_CHNL_STS: 0x60020200

The bit 0x20000 refers to OFLW_EARLY_VSYNC_ERR in the channel status register as per the datasheet and the mask definitions in the BSP

Thanks in advance,

Khaled

Re: [IMX8] ISI errors

joanxie — Tue, 17 Nov 2020 09:02:20 GMT

refer to the reference manual, maybe you can check the LATE_VSYNC_
ERR_EN in the CHNL_IER, it's better you tell me what operation or testing you do get these messages, then we can reproduce this and find the answer, just for LATE_VSYNC_
ERR_EN, I only find the description in the reference manual, you should already know it:

VSYNC timing (Late) error interrupt flag
Indicates that the VSYNC for the frame was detected later than expected. The resultant frame will have
correct data. The extra lines in frame will be ignored.
0b - No error
1b - VSYNC detected later than expected

Re: [IMX8] ISI errors

khaledbalbaa — Tue, 17 Nov 2020 09:32:34 GMT

Thanks a lot Joanxie, we were communicating the issue also with the deserializer supplier as we are connecting the I.MX8 with a deserializer from MAXIM and we found the the deserializer is sending the first frame with some corrupted data in its start, I guess this is the cause of the VSYNC interrupt from the ISI

Re: [IMX8] ISI errors

joanxie — Wed, 13 Jan 2021 09:32:09 GMT

sorry for missing this message, how about the status now?

Re: [IMX8] ISI errors

khaledbalbaa — Wed, 13 Jan 2021 10:06:31 GMT

no problem, still investigating with the Deserializer supplier