C
CAN: Controller Area Network
The Controller Area Network, or CAN, protocol is a serial communication protocol originally developed by Robert Bosch GmbH for use in serial communication networks in vehicles. Several major auto manufacturers are either currently using CAN networks in their vehicles or are developing them for future vehicles. In addition, CAN is becoming very popular for use in factory-floor automation-type industrial networks. The major players in industrial automation, including Allen-Bradley, Honeywell and Eaton Cutler-Hammer are all manufacturing CAN-based industrial control systems, and are publicizing their beliefs that the CAN protocol is the best solution for this type of control network.
The CAN specification addresses the lowest two layers of the ISO's Open Systems Interconnect (OSI) Reference model for communication protocols, the Data Link Layer and the Physical Layer. However, while certain aspects of the Physical Layer are addressed by the CAN protocol, its primary purpose is to define the aspects of the Media Access Control (MAC) sublayer and a small part of the Logical Link Control (LLC) sublayer of the Data Link Layer. Almost all aspects of the Physical Layer (data rate, choice of media, etc) are left to the user.
CCTV: Closed Caption Television
The closed caption television (CCTV) module is used in television receivers, set-top decoders, or VCRs conforming to the NTSC standard. A programmable data slicer (DSL) extracts closed-caption compatible data from an NTSC composite video signal for closed-caption and extended data services applications. Once the data is extracted an on-screen display system (OSD) displays the data on the television screen.
CGM: Clock Generator Module
The Clock Generator Module (CGM) is a 68HC08 module that generates two different clock signals from a user-selected source. The crystal clock signal is buffered by the CGM and used by the SCI baud rate generator and the COP watchdog timer. In addition, the output clock of the CGM, generated by either the crystal clock or an on-board phased-lock loop clock, is used by the SIM, which drives internal bus clocks. The on-board phased-lock loop can be used to generate maximum bus speed (8 MHz) cost-effectively (1 MHz to 16 MHz external crystal).
COP: Computer Operating Properly
CPU: Central Processing Unit
The Central Processing Unit (CPU) processes information in accordance with a program of instructions and data in a particular language called "machine code". The CPU controls all the system operations and provides control signals for enabling and disabling the various peripherals and I/O devices.In addition to the accumulator, the CPU's core has an index register, a 5-bit stack pointer, and a 5-bit condition code register. The instruction set features 10 uncomplicated addressing modes including 8 and 16-bit indexing from the 16-bit program counter. Bit manipulation instructions are provided to set, clear, test, or jump based on a bit value anywhere in the memory map. Math functions include add, subtract, and multiply.
Wait mode reduces power consumption by approximately 50% by discontinuing CPU processing. The clock continues to run in wait mode inorder to service interrupts immediately. Stop mode stops the clock and all internal processing to reduce power consumption to micoroamps. Both modes maintain memory and enable an interrupt to wake up the CPU.
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