Hi,
I am trying to capture Parallel data output by the OPT9221 on a host platform ( host CPU is iMX6 ). So far the host CPU is not detecting any data frames. To debug I am looking at the data output waveform.
One thing I have noticed is that the "Vertical Top Blanking time (tVTB) " is very large, it is more than 20 ms. I am trying to capture at 30 fps and I have measured the Data Output Clock is 24 MHz, so more than half the frame time is wasted just in Vertical Top Blanking. The controlling parameter for tVTB I found in the datasheet is "frm_blnk_size". (please correct me if I am wrong). But reading frm_blank_size shows that it is set to 0 (the default value). Why then do I have such a large tVTB in the output waveform? I also tried setting the frm_blank_size parameter to other values, such as 500 and 5000, but it did not seem to have any effect on the tVTB. Do we need to assert some sort of reset etc for the parameter to take effect?
The second thing that appears wrong in the output waveform is that there are more than 240 pulses on HD within each frame period (currently it is 600 pulses). Also, the number of Output Clock edges under each HD pulse is 512. I feel that something is not right with these numbers. The relevant parameters that I read from the OPT9221 are:
row_start = 0
row_end = 239
col_start = 0
col_end = 19
bin_row_count = 240
bin_col_count = 320
rows_to_merge = 1
cols_to_merge = 1
I would appreciate if anyone could help me understand the problem.
Best regards,
Ibtsam Haq
