Linux driver for Renesas TW9992
The
is a low Power NTSC/PAL Video Decoder with Differential CVBS Inputs and
MIPI-CSI2 Output Interface.
It can be connected to Raspberry Pi camera interface or other MIPI-CSI2 receiver.
To compile and install:
cd driver
make crash
There is a test program in src/fb.c. It works on console framebuffer. Just gcc fb.c and ./a.out
There are special v4l controls "setaddr", "getreg" and "setreg". You can use them to peek and poke i2c registers. For example get value of register 3
v4l2-ctl -c setaddr=0x03; v4l2-ctl -C getreg | sed 's/getreg:/obase=2;/' | bc
1101001
bc did not display value 0 on bit 7, meaning "0 = Video detected."
Register 3 bits:
| Bit | Description |
|---|---|
| 7 VDLOSS R | 1 = Video not present. (Sync is not detected in number of line periods specified by MISSCNT register) |
| 0 = Video detected. | |
| 6 HLOCK R | 1 = Horizontal sync PLL is locked to the incoming video source. |
| 0 = Horizontal sync PLL is not locked. | |
| 5 SLOCK R | 1 = Subcarrier PLL is locked to the incoming video source. |
| 0 = Subcarrier PLL is not locked. | |
| 4 FIELD R | 1 = Even field is being decoded. |
| 0 = Odd field is being decoded. | |
| 3 VLOCK R | 1 = Vertical logic is locked to the incoming video source. |
| 0 = Vertical logic is not locked. | |
| 2 Reserved R | Reserved - |
| 1 MONO R | 1 = No color burst signal detected. |
| 0 = Color burst signal detected. | |
| 0 DET50 R | 0 = 60Hz source detected |
| 1 = 50Hz source detected |
Get the datasheet for register info.
Example module for Raspberry Pi:
An EasyEDA project can be found in https://oshwlab.com/jarkko.sonninen/tw9992-pmod-1-0