Intel 82830M GMCH - Page 48

48 Intel® Digital Set Top Box Display Driver
User’s Guide for Microsoft* Windows* CE 5.0
7.1.1.18 ICEGD_ESCAPE_I2C_ACCESS
Input Data Structure Output Data Structure Notes
esc_i2c_access_t unsigned char
In case of read operation, data is returned in output buffer.
Write operation data is retrieved from the esc_i2c_access_t
input buffer.
Description
This escape code is used to access I2C. It can implement a read or write operation by setting the mode.
Input Data Structure Definition
Please refer icegd_public_escape.h for details about esc_i2c_access_t;
Example
esc_i2c_config_t i2c_config;
esc_i2c_access_t i2c_access;
unsigned char data;
unsigned char data2;
memset(&i2c_config, 0, sizeof(esc_i2c_config_t));
memset(&i2c_access, 0, sizeof(esc_i2c_access_t));
//the data is only for cx892.
// please refer to special documents for different cards
i2c_config.bus = 4;
i2c_config.dab = 0x88;
i2c_config.speed = 200;
/* Configure I2C Bus access */
ExtEscape(
Hdc,
ICEGD_ESCAPE_I2C_CONFIG,
sizeof(esc_i2c_config_t),
(LPCSTR)&i2c_config,
0,
NULL);
i2c_access.addr = 0x54;
i2c_access.mode = INTEL_I2C_MODE_READ;
/* Read a character from address 0x54 */
ExtEscape(
Hdc,
ICEGD_ESCAPE_I2C_ACCESS,
sizeof(esc_i2c_access_t),
(LPCSTR)&i2c_access,
sizeof(unsigned char),
(LPSTR)&data);
/* Write data 140 back */
i2c_access.mode = INTEL_I2C_MODE_WRITE;
i2c_access.data = 140;
ExtEscape(
Hdc,
ICEGD_ESCAPE_I2C_ACCESS,
sizeof(esc_i2c_access_t),
(LPCSTR)&i2c_access,
sizeof(unsigned char),
(LPSTR)&data);
printf("%d\n",data);