Texas Instruments TMS320 2833 Series User Manual

FSR
GSYNC
synchronization
andclock
detection
Framepulse
SRGR1
[CLKGDV]
CLKSRG
0
1
CLKXP
MCLKXpin
CLKRP
MCLKRpin
0
1
LSPCLK
SRGR2[CLKSM]
0
1
PCR
[SCLKSME]
SRGR1
[FWID]
CLKG
FSG
pulse
Frame
SRGR2
[FPER]
÷
Reserved
/(CLKGDV+1)
www.ti.com McBSP Sample Rate Generator
671
SPRUI07–March 2020
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Multichannel Buffered Serial Port (McBSP)
12.4.1 Block Diagram
Figure 12-17. Conceptual Block Diagram of the Sample Rate Generator
The source clock for the sample rate generator (labeled CLKSRG in the diagram) can be supplied by the
LSPCLK, or by an external pin (MCLKX or MCLKR ). The source is selected with the SCLKME bit of PCR
and the CLKSM bit of SRGR2. If a pin is used, the polarity of the incoming signal can be inverted with the
appropriate polarity bit (CLKXP of PCR or CLKRP of PCR).
The sample rate generator has a three-stage clock divider that gives CLKG and FSG programmability.
The three stages provide:
• Clock divide-down. The source clock is divided according to the CLKGDV bits of SRGR1 to produce
CLKG.
• Frame period divide-down. CLKG is divided according to the FPER bits of SRGR2 to control the period
from the start of a frame-pulse to the start of the next pulse.
• Frame-synchronization pulse-width countdown. CLKG cycles are counted according to the FWID bits
of SRGR1 to control the width of each frame-synchronization pulse.
NOTE: The McBSP cannot operate at a frequency faster than ½ the source clock frequency. You
must choose an input clock frequency and a CLKGDV value such that CLKG is less than or
equal to ½ the source clock frequency.
In addition to the three-stage clock divider, the sample rate generator has a frame-synchronization pulse
detection and clock synchronization module that allows synchronization of the clock divide down with an
incoming frame-synchronization pulse on the FSR pin. This feature is enabled or disabled with the
GSYNC bit of SRGR2.
For details on getting the sample rate generator ready for operation, see Section 12.4.4.

Texas Instruments TMS320 2833 Series Specifications

General

Brand	Texas Instruments
Model	TMS320 2833 Series
Category	Controller
Language	English