McBSP Interface Signals and Registers
11-11
Multichannel Buffered Serial Ports
Figure 11–3.Pin Control Register (PCR)
31 16
reserved
R, +0
15 14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Rsvd
XIOEN
RIOEN
FSXM
FSRM
CLKXM
CLKRM
Rsvd
CLKS_STAT
DX_STAT
DR_STAT
FSXP
FSRP
CLKXP
CLKRP
R,+0
RW,+0
RW,+0
RW,+0
RW,+0
RW,+0
RW, +0
R,+0
RW,+0
RW,+0
R,+0
RW,+0
RW,+0
RW,+0
RW,+0
Table 11–6.
Pin Control Register (PCR) Field Descriptions
Name
Function
Section
RIOEN
Receiver in general-purpose I/O mode
only when RRST = 0 in SPCR
RIOEN = 0: DR and CLKS pins are not general-purpose inputs. FSR and CLKR are
not general-purpose I/Os and perform serial port operation.
RIOEN = 1: DR and CLKS pins are general-purpose inputs. FSR and CLKR are general-
purpose I/Os. These serial port pins do not perform serial port operation.
11.8
XIOEN
Transmitter in general-purpose I/O mode
only when XRST = 0 in SPCR
XIOEN = 0: CLKS pin is not a general-purpose input. DX pin is not a general purpose
output. FSX and CLKX are not general-purpose I/Os.
XIOEN = 1: CLKS pin is a general-purpose input. DX pin is a general-purpose output.
FSX and CLKX are general-purpose I/Os. These serial port pins do not per-
form serial port operation.
11.8
FSXM
Transmit frame synchronization mode
FSXM = 0: Frame synchronization signal is provided by an external source. FSX is
an input pin.
FSXM = 1: Frame synchronization generation is determined by the sample rate gen-
erator frame synchronization mode bit FSGM in the SRGR.
11.5.3.3
and
11.8
FSRM
Receive frame synchronization mode
FSRM = 0: Frame synchronization signals are generated by an external device.
FSR is an input pin.
FSRM = 1: Frame synchronization signals are generated internally by the sample rate
generator. FSR is an output pin except when GSYNC = 1 (see section
11.5.1.1) in SRGR.
11.5.3.2
and
11.8