67 lines
4.5 KiB
ReStructuredText
67 lines
4.5 KiB
ReStructuredText
|
Common Problems with DVP
|
||
|
|
=================================
|
||
|
|
|
||
|
|
|
||
|
|
:link_to_translation:`zh_CN:[中文]`
|
||
|
|
|
||
|
|
|
||
|
|
1. Introduction
|
||
|
|
---------------------------------
|
||
|
|
|
||
|
|
This section mainly describes the common problems and solutions encountered during debugging and using DVP cameras.
|
||
|
|
|
||
|
|
Q: Unable to recognize camera
|
||
|
|
|
||
|
|
A: Use `dvp <../../projects/peripheral/dvp/index. html>`_ Sample project, testing the adapted sample sensor, gc2145,
|
||
|
|
If it cannot be recognized, it indicates that there is an error in the parameter configuration of the newly adapted sensor in dvp_xxx.c.
|
||
|
|
The most fundamental issue is the I2C read-write address and CHIP_ID of the new sensor.
|
||
|
|
If even gc2145 cannot recognize it, check whether the sensor power supply DVDD and IOVDD meet the protocol requirements,
|
||
|
|
whether the GPIO controlling the power on the hardware is also GPIO28, and whether I2C is also corresponding to GPO0 and GPO1.
|
||
|
|
In addition, attention should be paid to contact issues, which may also be due to insufficient physical connection, resulting in malfunction.
|
||
|
|
|
||
|
|
Q: Abnormal image output and printing: "Sensor's yuyv data resolution is not right".
|
||
|
|
|
||
|
|
A: The DVP data collected by the main control does not match the configured resolution. The VSync/HSync/PCLK signals can be captured through a logic analyzer.
|
||
|
|
The following conditions must be followed: if the resolution configured for the main control is 640X480, then a VSync must contain 480 HSync pulses internally,
|
||
|
|
and an HSync must contain 640 * 2=1280 PCLK pulses internally.
|
||
|
|
If it does not meet the requirements, it will inevitably result in abnormal graphics.
|
||
|
|
This problem may be caused by poor physical contact, and needs to be unplugged and reinstalled.
|
||
|
|
Possible data collection anomalies may be caused by inconsistent line sequence with the default BK7258.
|
||
|
|
Perhaps due to electromagnetic interference from the board, the sampling of the main control may be inaccurate in PCLK. A pull-up filter capacitor 8-22pf can be connected to PLK.
|
||
|
|
|
||
|
|
Q: Abnormal image output and printing: "sensor FIFO is full".
|
||
|
|
|
||
|
|
A: The main control is receiving DVP data too slowly, causing sensor FIFO overflow. The solution can be tried:
|
||
|
|
Reduce frame rate/reduce resolution/increase YUV_BUF hardware module clock (current default JPEG: 120MHz, YUV_BUF:120MHz, H264:120MHz).
|
||
|
|
|
||
|
|
Q: Abnormal image output and printing: "JPEG code rate is slow than sensor data rate".
|
||
|
|
|
||
|
|
A: Indicates that the encoding speed is too slow. The solution can be to try reducing the frame rate/resolution/increasing the clock of the encoding hardware module
|
||
|
|
(currently default JPEG: 120MHz H264:120MHz).
|
||
|
|
|
||
|
|
Q: Abnormal image output and printing: "h264 encode error".
|
||
|
|
|
||
|
|
A: Indicates H264 encoding error, which may be caused by the sensor's frame gap time being too low, resulting in abnormal control;
|
||
|
|
It is also possible that the previous frame has not been fully encoded before the start of the H264 encoding for the new frame.
|
||
|
|
In this case, the software code has already covered and the relevant hardware modules can be reset directly.
|
||
|
|
|
||
|
|
Q: I2C abnormality after switching, camera cannot communicate normally.
|
||
|
|
|
||
|
|
A: This situation usually occurs when other peripherals share a set of I2C with DVP, and this I2C is cut off and used by other peripherals;
|
||
|
|
It is recommended to use software I2C to prevent the problem of not working after reuse. Open the software I2C function macro control:
|
||
|
|
|
||
|
|
+--------------------+---------------+------------------------------------------------+
|
||
|
|
| marco | value | implication |
|
||
|
|
+--------------------+---------------+------------------------------------------------+
|
||
|
|
| CONFIG_SIM_I2C | Y | Enable software to simulate I2C functionality |
|
||
|
|
+--------------------+---------------+------------------------------------------------+
|
||
|
|
|
||
|
|
Q: Configure to h264/JPEG encoding mode, abnormal printing occurs: "···· size no match ····"
|
||
|
|
|
||
|
|
A: In general, the length of data transferred by DMA is not consistent with the actual encoding length.
|
||
|
|
This will result in the software discarding such erroneous frames by default to prevent screen flickering and other issues, and resetting the corresponding module.
|
||
|
|
|
||
|
|
Q: The perspective is not in the center when creating the image.
|
||
|
|
|
||
|
|
A: This problem is caused by configuring the parameters (registers) of DVP. It is recommended to find an engineer from the sensor factory to reconfigure it.
|
||
|
|
Currently, the configuration provided by the SDK only guarantees normal image output.
|