CTM-4102 2 Channel PCM Output Card

CALCULEX produces a number of different PCI bus circuit boards that provide a variety of input and output capabilities. The CTM-4102 module can generate two independent PCM streams at up to 20 megabits per second per channel.

Each PCM output channel operates independently from the other. For normal operations, the CTM-4102 performs the inverse function of the CTM-1102 input module on two channels. Data previously recorded in IRIG 107-97 packet format is serialized, repacked if the data was unpacked during recording, and output with a bit clock at the appropriate data rate. The user specifies separately for each channel the approximate data rate and the bit length of each word in the PCM frame. The actual output bit clock rate is produced from fine time and offset words in the packet headers. When multiple channels on one or more CTM-1102 PCM input modules were recorded simultaneously, multiple CTM-4102 modules can be operated in a mode which reestablishes the original phase relationship between the channels. For simulation mode operations, each channel is programmed to output a repeated sequence at a specified rate while external processors on the PCI bus dynamically modify selected words in the output buffers.

The PCI bus interface on the CTM-4102 supports both initiator and target transfers. For initiator transfers, the module arbitrates for use of the PCI bus and when granted, performs single cycle or burst transfers as directed to the designated target addresses. For target transfers, the buffers on the CTM-4102 are mapped into the PCI bus address space and an external bus initiator performs either single cycle or burst accesses with the module.