Src Mute-Out Interrupt; Sample Rate Ratio; Programming Summary - Analog Devices SHARC ADSP-21368 Hardware Reference Manual

For information on using the SRU, see
SRUs" on page
page 4-18.

SRC Mute-Out Interrupt

Once the SRC is locked (after 4K input samples), the corresponding
SRCx_MUTE_OUT
interrupt. From this point, the SRC produces output serial
DAI_INTH/L
data at the output sampling frequency. The SRC mute signals can be used
to generate interrupts on their leading edge, falling edge, or both, depend-
ing on how the

Sample Rate Ratio

Once the SRC mute interrupt has triggered, the
isters can be read to find the ratio of output to input sampling frequency.
This ratio is reported in 4.11 (integer.fraction) format.

Programming Summary

Since the SRC data is not available to the core, programming the SRC
peripheral involves simply connecting the SRU to the on-chip (serial ports
or input data port) or off-chip (DAI pins) serial devices. These devices
provide the clock and data to be converted, and select the desired operat-
ing mode in the SRC control register. This setup can be accomplished in
two steps.
1. Connect each of the four SRCs to their two serial clocks
(
SRCx_CLK_IP_I
(
SRCx_FS_IP_I
(
SRCx_DAT_IP_I
ADSP-21368 SHARC Processor Hardware Reference
Asynchronous Sample Rate Converter
4-15, and "DAI/SRU1 Connection Groups" on
bit in the
DAI_IRPTL_H/L
registers are programmed.
DAI_IRPT_RE/FE
,
SRCx_CLK_OP_I
,
SRCx_FS_OP_I
) and one data output (
"Making Connections in the
register is set. This generates the
SRCRAT0
) and frame sync inputs
). Also connect one data input
SRCx_DAT_OP_O
and reg-
SRCRAT1
) in the SRU.
10-23