User's Manual

FLC-BTM805 Datasheet
Flaircomm Microelectronics Confidential
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Figure 9: Multi-Slot Operation with Two Slots and 8-bit Companded Samples
4.3.1.5 GCI Interface
BTM805 is compatible with the General Circuit Interface (GCI), a standard synchronous 2B+D
ISDN timing interface. The two 64Kbps B channels are accessed when this mode is configured.
Figure 10: GCI Interface
The start of a frame is indicated by the rising edge of PCM_SYNC and runs at 8kHz.
4.3.1.6 Slots and Sample Formats
BTM805receives and transmits on any selection of the first four slots following each sync pulse. Slot
durations are either 8 or 16 clock cycles.
 8 clock cycles for 8-bit sample formats.
 16 clock cycles for 8-bit, 13-bit or 16-bit sample formats.
BTM805 supports:
 13-bit linear, 16-bit linear and 8-bit μ -law or A-law sample formats.
 A sample rate of 8ksamples/s.