Ch7026 debugging pen

I. IC functions

Ch7026 is a TV signal generator IC that can output sdtv, HDTV, and vga TV signals.

Ii. debugging instructions

1. Because the ch7026 register control is implemented through I2C, We need to debug I2C before debugging. Here I will not elaborate on it, mainly emphasizing the I2C address: the address of the ch7026 device is related to the 5th-pin as. If the grounding address is 76, this is the address with no clearance.ProgramWe need to use 0xec.

2. There are two types of ch7026 Reset: hardware reset and software reset. In general, we can directly increase the reset foot, and then reset it by writing the 0x03 register.

3. Next, determine the input RGB digits, the input parameter values (total HTI lines, visible Hai Lines, Ho lines, HW pulse width, VTI, vai, Vo, VW, lcdclk value), which can be configured according to the driver. (REG: 0xf ~ Ox1a)

4. Determine the output timing, (HTO, Hao, hoo, hwo, VTO, VAO, Voo, VWO), Reg: 0x1b ~ 0x26.

{0x1b, 0x13 },//
{0x1c, 0x7a}, // hao
{0x1d, 0xb1}, // HTO
// {0x1e, 0x00 },//
{0x1f, 0x01}, // hoo

{0x20, 0x0a}, // hwo
// ---- Vertical
{0x21, 0x51 },
{0x22, 0xdb}, // VAO
{0x23, 0xa8}, // VTO
// {0x24, 0x0 },
{0x25, 0x0f}, // Voo-> 16
{0x26, 0x04}, // VWO ---> 4

The VGA output is 800*600 scale, but the display is displayed. I don't think the effect is good. Improvements are also expected.

5. clock register: 0x41 ~ 0x52

The external clock source is 13 m: VGA clock is configured as follows:

{0x41, 0xa2 },
{0x4d, 0x03 },
{0x4e, 0x0f },
{0x4f, 0x8e },
{0x50, 0x92 },
{0x51, 0x51 },
{0x52, 0x12 },
{0x53, 0x13 },

6. Location Register: 0x33 ~ 0x36

 

Ch7026 has the test mode. You can use the test mode to determine whether the problem is output or input. The test mode is to generate a colorful output through the chip.

 

Debugging ch7026 is still faster, and the tool can be downloaded in my space.