User Manual

Bluegiga Proprietary Version 1.0
29
The start of frame is indicated by PCM_SYNC and runs at 8kHz. With WRAP THOR 2022-1 in
Slave mode, the frequency of PCM_CLK can be up to 4.096MHz. In order to configure the PCM
interface to work in GCI mode it is necessary to set GCI_MODE bit in PSKEY_PCM_CONFIG32.
The SAMPLE_FORMAT bits should be set to 0x0b01 to allow for the double clocking of each.
12.5 S
LOTS AND SAMPLE FORMATS
WRAP THOR 2022-1 can receive and transmit on any selection of the first four slots following
each sync pulse. Slot durations can be either 8 or 16 clock cycles. Durations of 8 clock cycles may
only be used with 8-bit sample formats. Durations of 16 clocks may be used with 8, 13 or 16-bit
sample formats.
WRAP THOR 2022-1 supports 13-bit linear, 16-bit linear and 8-bit o-law or A-law sample formats.
The sample rate is 8ksamples/s. The bit order may be little or big endian. When 16-bit slots are
used, the 3 or 8 unused bits in each slot may be filled with sign extension, padded with zeros or a
programmable 3-bit audio attenuation compatible with some Motorola CODECs.
Figure 22: 16-bit Slot Length and Sample Formats