Set The Receive Companding Mode; Unexpected Frame-Synchronization Pulse With (R/X)Fig; Unexpected Frame-Synchronization Pulse With (R/X)Fig = 1; Register Bits Used To Set The Receive Companding Mode - Texas Instruments Concerto F28M35 Series Technical Reference Manual

Receiver Configuration
When RFIG = 0, an unexpected FSR pulse causes the McBSP to discard the contents of RSR[1,2] in
favor of the new incoming data. Therefore, if RFIG = 0 and an unexpected frame-synchronization pulse
occurs, the serial port:
1. Aborts the current data transfer
2. Sets RSYNCERR in SPCR1 to 1
3. Begins the transfer of a new data word
For more details about the frame-synchronization error condition, see
Frame-Synchronization Pulse.
15.8.10.2 Examples of Effects of RFIG
Figure 15-43 shows an example in which word B is interrupted by an unexpected frame-synchronization
pulse when (R/X)FIG = 0. In the case of reception, the reception of B is aborted (B is lost), and a new data
word (C in this example) is received after the appropriate data delay. This condition is a receive
synchronization error, which sets the RSYNCERR bit.
Figure 15-43. Unexpected Frame-Synchronization Pulse With (R/X)FIG = 0
CLK(R/X)
FS(R/X)
DR
DX
(R/X)SYNCERR
In contrast with Figure
synchronization signals are ignored (when (R/X)FIG = 1). Here, the transfer of word B is not affected by
an unexpected pulse.
Figure 15-44. Unexpected Frame-Synchronization Pulse With (R/X)FIG = 1
CLK(R/X)
FS(R/X)
D(R/X)
(R/X)SYNCERR

15.8.11 Set the Receive Companding Mode

The RCOMPAND bits (see
chosen for McBSP reception.
Table 15-30. Register Bits Used to Set the Receive Companding Mode
Register Bit Name
RCR2 4-3 RCOMPAND Receive companding mode
1084
C28 Multichannel Buffered Serial Port (McBSP)
Frame synchronization aborts current transfer
A0 B7 B6 C7 C6
A0 B7 B6 B7 B6
15-43, Figure 15-44 shows McBSP operation when unexpected frame-
A0 B7 B6 B5 B4
Table 15-30) determine whether companding or another data transfer option is
Function
Modes other than 00b are enabled only when the appropriate RWDLEN is
000b, indicating 8-bit data.
RCOMPAND = 00 No companding, any size data, MSB received first
RCOMPAND = 01 No companding, 8-bit data, LSB received first (for details,
see
RCOMPAND = 10 μ-law companding, 8-bit data, MSB received first
RCOMPAND = 11 A-law companding, 8-bit data, MSB received first
Copyright © 2012–2019, Texas Instruments Incorporated
Section
New data received
C5 C4 C3 C2
Current data retransmitted
B5 B4 B3 B2
Frame synchronization ignored
B3 B2 B1 B0
Section 15.8.11.4).
SPRUH22I – April 2012 – Revised November 2019
www.ti.com
15.5.3, Unexpected Receive
C1 C0 D7 D6
B1 B0 C7 C6
C7 C6 C5 C4
Type
R/W
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Reset
Value
00