User manual

Serial Communications Controllers (SCCs)
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor 20-5
Figure 20-3 shows GSMR_L.
Table 20-2 describes GSMR_L fields.
28–29 SYNL Sync length (BISYNC and transparent mode only). See the data synchronization register (DSR)
definition in Section 23.9, “Sending and Receiving the Synchronization Sequence,” (BISYNC) and
Section 24.4.1.1, “In-Line Synchronization Pattern,” (transparent).
00 An external sync (CD
) is used instead of the sync pattern in the DSR.
01 4-bit sync. The receiver synchronizes on a 4-bit sync pattern stored in the DSR. This sync and
additional syncs can be stripped by programming the SCC’s parameter RAM for character
recognition.
10 8-bit sync. Should be chosen along with the BISYNC protocol to implement mono-sync. The
receiver synchronizes on an 8-bit sync pattern in the DSR.
11 16-bit sync. Also called BISYNC. The receiver synchronizes on a 16-bit sync pattern stored in
the DSR.
30 RTSM RTS
mode. Determines whether flags or idles are to be sent. Can be changed on-the-fly.
0 Send idles between frames as defined by the protocol and the TEND bit. RTS
is negated between
frames (default).
1 Send flags/syncs between frames according to the protocol. RTS
is always asserted whenever
the SCC is enabled.
31 RSYN Receive synchronization timing (totally transparent mode only).
0 Normal operation.
1 If CDS = 1
, CD should be asserted on the second bit of the Rx frame rather than on the first.
012345678 101112131415
Field — EDGE TCI TSNC RINV TINV TPL TPP TEND TDCR
Reset 0000_0000_0000_0000
R/W R/W
Addr 0x0x11A00 (SCC1); 0x0x11A20 (SCC2); 0x0x11A40 (SCC3); 0x0x11A60 (SCC4)
16 17 18 20 21 23 24 25 26 27 28 31
Field RDCR RENC TENC DIAG ENR ENT MODE
Reset 0000_0000_0000_0000
R/W R/W
Addr 0x11A02 (SCC1); 0x11A22 (SCC2); 0x11A42 (SCC3); 0x11A62 (SCC4)
Figure 20-3. GSMR_L—General SCC Mode Register (Low Order)
Table 20-2. GSMR_L Field Descriptions
Bit Name Description
0 — Reserved, should be cleared.
Table 20-1. GSMR_H Field Descriptions (continued)
Bit Name Description