I2C(also IIC; the "2" is superscripted) Inter-Integrated Circuit Bus -- A moderate-speed serial communications bus originally invented by Philips in the early 1980s for consumer-electronics applications, such as inter-chip communication in a television set or high-end stereo. The I2C bus has recently appeared on PCs in video capture boards and similar devices, as well as (surprisingly) SDRAM DIMMs (for the on-board serial EEPROM). The ACCESS.bus is a derivative of the I2C bus which forms the physical layer of the Universal Serial Bus. Similary, the SMBus (System Management Bus) also uses I2C as its physical layer. 86h/28h/C0h U - ITT VPX 32xx - FP - Horizontal RetraceWhen a monitor has finished displaying a single scan line, it must move it electron beam(s) back to the left edge of the CRT, during which time it turns off the beam. On the original CGAColor Graphics Adapter (and some early clones), the only time one could access the display memory without causing "snow" was during the horizontal or vertical retrace periods, as the display adapter was not itself accessing the display memory during those times. See also Vertical Retrace. Frequency Desc: this appears to be the base frequency from which the HPLL attempts to lock onto the video signal (default = 700dec) SeeAlso: I2C(also IIC; the "2" is superscripted) Inter-Integrated Circuit Bus -- A moderate-speed serial communications bus originally invented by Philips in the early 1980s for consumer-electronics applications, such as inter-chip communication in a television set or high-end stereo. The I2C bus has recently appeared on PCs in video capture boards and similar devices, as well as (surprisingly) SDRAM DIMMs (for the on-board serial EEPROM). The ACCESS.bus is a derivative of the I2C bus which forms the physical layer of the Universal Serial Bus. Similary, the SMBus (System Management Bus) also uses I2C as its physical layer. 86h/28h,I2C(also IIC; the "2" is superscripted) Inter-Integrated Circuit Bus -- A moderate-speed serial communications bus originally invented by Philips in the early 1980s for consumer-electronics applications, such as inter-chip communication in a television set or high-end stereo. The I2C bus has recently appeared on PCs in video capture boards and similar devices, as well as (surprisingly) SDRAM DIMMs (for the on-board serial EEPROM). The ACCESS.bus is a derivative of the I2C bus which forms the physical layer of the Universal Serial Bus. Similary, the SMBus (System Management Bus) also uses I2C as its physical layer. 86h/29h