SCC Programming Reference
E-2
MC68360 USER’S MANUAL
MOTOROLA
NOTE: The offset is from the MC68302
base address + ($400 for SCC1, $500 for SCC2, or $600 for SCC3).
NOTE: The offset is from the MC68302 base address + ($400 for SCC1, $500 for SCC2, or $600 for SCC3).
Table E-1 (a). HDLC Programming Mode
Receive and Transmit Buffer Descriptors for SCCx
Initialized
by User
Yes
Offset
Hex
00
02
04
06
08
0A
0C
0E
10
12
14
16
18
1A
1C
1E
20
22
24
26
28
2A
2C
2E
30
32
34
36
38
3A
3C
3E
Name
Initialized
by User
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Offset
Hex
40
42
44
46
48
4A
4C
4E
50
52
54
56
58
5A
5C
5E
60
62
64
66
68
6A
6C
6E
70
72
74
76
78
7A
7C
7E
Name
Yes
Yes
Yes
Rx BD 0 Control/Status
Rx BD 0 Data Count
Rx BD 0 Data Pointer (High Word)
Rx BD 0 Data Pointer (Low Word)
Rx BD 1 Control/Status
Rx BD 1 Data Count
Rx BD 1 Data Pointer (High Word)
Rx BD 1 Data Pointer (Low Word)
Rx BD 2 Control/Status
Rx BD 2 Data Count
Rx BD 2 Data Pointer (High Word)
Rx BD 2 Data Pointer (Low Word)
Rx BD 3 Control/Status
Rx BD 3 Data Count
Rx BD 3 Data Pointer (High Word)
Rx BD 3 Data Pointer (Low Word)
Rx BD 4 Control/Status
Rx BD 4 Data Count
Rx BD 4 Data Pointer (High Word)
Rx BD 4 Data Pointer (Low Word)
Rx BD 5 Control/Status
Rx BD 5 Data Count
Rx BD 5 Data Pointer (High Word)
Rx BD 5 Data Pointer (Low Word)
Rx BD 6 Control/Status
Rx BD 6 Data Count
Rx BD 6 Data Pointer (High Word)
Rx BD 6 Data Pointer (Low Word)
Rx BD 7 Control/Status
Rx BD 7 Data Count
Rx BD 7 Data Pointer (High Word)
Rx BD 7 Data Pointer (Low Word)
Tx BD 0 Control/Status
Tx BD 0 Data Count
Tx BD 0 Data Pointer (High Word)
Tx BD 0 Data Pointer (Low Word)
Tx BD 1 Control/Status
Tx BD 1 Data Count
Tx BD 1 Data Pointer (High Word)
Tx BD 1 Data Pointer (Low Word)
Tx BD 2 Control/Status
Tx BD 2 Data Count
Tx BD 2 Data Pointer (High Word)
Tx BD 2 Data Pointer (Low Word)
Tx BD 3 Control/Status
Tx BD 3 Data Count
Tx BD 3 Data Pointer (High Word)
Tx BD 3 Data Pointer (Low Word)
Tx BD 4 Control/Status
Tx BD 4 Data Count
Tx BD 4 Data Pointer (High Word)
Tx BD 4 Data Pointer (Low Word)
Tx BD 5 Control/Status
Tx BD 5 Data Count
Tx BD 5 Data Pointer (High Word)
Tx BD 5 Data Pointer (Low Word)
Tx BD 6 Control/Status
Tx BD 6 Data Count
Tx BD 6 Data Pointer (High Word)
Tx BD 6 Data Pointer (Low Word)
Tx BD 7 Control/Status
Tx BD 7 Data Count
Tx BD 7 Data Pointer (High Word)
Tx BD 7 Data Pointer (Low Word)
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Table E-1 (b). HDLC Programming Model (Continued)
General Parameter and HDLC Protocol-Specific RAM for SCCx
Initialized
by User
Yes
Yes
Offset
Hex
80
82
84
Name
Initialized by
User
Yes
Offset
Hex
A2
A4
A6
Name
RFCR
TFCR
CRC_Mask_H
Temp Transmit CRC Low
Temp Transmit CRC High
MRBLR
Rx Internal State
86
Reserved
Rx Internal Buffer
No.
Yes
A8
DISFC
88
8A
8C
8E
90
Rx Internal Data Pointer (High Word)
Rx Internal Data Pointer (Low Word)
Rx Internal Byte Count
Rx Temp
Tx Internal State
Yes
AA
CRCEC
Yes
Yes
Yes
AC
AE
B0
ABTSC
NMARC
RETRC
92
Reserved
Tx Internal Buffer
No.
Yes
B2
MFLR
94
96
98
9A
9C
9E
A0
Tx Internal Data Pointer (High Word)
TX Internal Data Pointer (Low Word)
Tx Internal Byte Count
Tx Temp
Temp Receive CRC Low
Temp Receive CRC High
CRC_Mask_L
B4
MAX_cnt
Yes
Yes
Yes
Yes
Yes
B6
B8
BA
BC
BE
HMASK
HADDR1
HADDR2
HADDR3
HADDR4
Yes