Programmable Clock and Framing
11-66
11.5.4.2 Single-Rate ST-BUS Clock
This example is the same as the ST-BUS example except for the following
items:
-
CLKGDV = 0: CLKS drives CLK(R/X)_int without any divide down (single-
rate clock).
-
CLKSP = 0: The rising edge of CLKS generates internal clocks CLKG and
CLK(R/X)_int.
Figure 11–44.
Single-Rate Clock Example
E2B7
E1B0
E1B1
E1B2
E1B3
E1B4
E1B5
E1B6
E1B7
E2B7
E1B0
E1B1
E1B2
E1B3
E1B4
E1B5
E1B6
E1B7
E32B0
CLKG, CLKR_int,
CLKX_int (first FSR)
DR, DX
(subsequent FSR)
CLKG, CLKR_int,
CLKX_int
(subsequent FSR)
DR, DX (first FSR)
FSG, FSR_int, FSX_int
FSR external
CLKS
Sample point
The rising edge of CLKS detects the external FSR. This external frame sync
pulse resynchronizes the internal McBSP clocks and generates the frame sync
for internal use. The internal frame sync is generated so that it is wide enough
to be detected on the falling edge of the internal clocks.