SCC BISYNC Mode
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
23-4 Freescale Semiconductor
GSMR[MODE] determines the protocol for each SCC. The SYN1–SYN2 synchronization characters are
programmed in the DSR (see Section 20.1.3, “Data Synchronization Register (DSR).”) The BISYNC
controller uses the same basic data structure as other modes; receive and transmit errors are reported
through their respective BDs. There are two basic ways to handle BISYNC channels:
The controller inspects the data on a per-byte basis and interrupts the core each time a byte is
received.
The controller can be programmed so software handles the first two or three bytes. The controller
directly handles subsequent data without interrupting the core.
23.5 SCC BISYNC Commands
Transmit and receive commands are issued to the CP command register (CPCR). Transmit commands are
described in Table23-2.
0x40 BDLE Hword BISYNC DLE register. Contains the value to be sent as the first byte of a
DLE–SYNC pair and stripped on receive. See Section23.8, “SCC BISYNC DLE
Register (BDLE).”
0x42 CHARACTER1 Hword Control character 1–8. These values represent control characters that the
BISYNC controller recognizes. See Section23.6, “SCC BISYNC Control
Character Recognition.”
0x44 CHARACTER2 Hword
0x46 CHARACTER3 Hword
0x48 CHARACTER4 Hword
0x4A CHARACTER5 Hword
0x4C CHARACTER6 Hword
0x4E CHARACTER7 Hword
0x50 CHARACTER8 Hword
0x52 RCCM Hword Receive control character mask. Masks CHARACTER
n
comparison so control
character classes can be defined. Setting a bit enables and clearing a bit masks
comparison. See Section23.6, “SCC BISYNC Control Character Recognition.”
1From SCC
x
base address. See Section20.3.1, “SCC Base Addresses.”
Table23-1. SCC BISYNC Parameter RAM Memory Map
Offset 1Name Width Description