8-2
IIC
Figure 47. 10-Bit Addressing
8.3 IIC Register Map
IIC registers are accessed via memory locations 0xFF6X_000Y, where X=2 for the IIC0 interface and X=3
for the IIC1 interface. Y designates the register within the IIC0 or IIC1 interface to be accessed.
The master data buffer is actually a 1-byte wide by 4-bytes deep first-in/first-out (FIFO) buffer. When a byte
is written to the master data buffer address, it goes into the fourth stage of the FIFO. If the third stage is
empty, the data just written into the fourth stage is moved into the third stage at the very next system clock.
This process is repeated for the second and first stages at each successive system clock. The byte will
move through the buffer until it bumps into a stage that has a valid byte of data. The data contained in this
buffer is either sent out onto the IIC bus when the IIC interface is performing a write operation, or is
received from the IIC bus when the IIC interface is performing a read operation.
Table 78. IIC Registers
Facility Name
Mnemonic
CPC700
Map
Addres
s (hex)
Type
Affected by
Reset
Size
(bits)
Master Data Buffer
IICxMDBUF
FF6X_0000
0x0
R/W
Yes- cleared
8,16
reserved
Reserved
FF6X_0001
0x1
Slave Data Buffer
IICxSDBUF
FF6X_0002
0x2
R/W
Yes- cleared
8,16
reserved
Reserved
FF6X_0003
0x3
Lo Master Address
IICxLMADR
FF6X_0004
0x4
R/W
No
8
Hi Master Address
IICxHMADR
FF6X_0005
0x5
R/W
No
8
Control
IICxCNTL
FF6X_0006
0x6
R/W
Yes- cleared
8
Mode Control
IICxMDCNTL
FF6X_0007
0x7
R/W
Yes- cleared
8
Status
IICxSTS
FF6X_0008
0x8
R/W
Yes- cleared
7
Extended Status
IICxEXTSTS
FF6X_0009
0x9
R/W
Yes- cleared
8
Lo Slave Address
IICxLSADR
FF6X_000A
0xA
R/W
No
8
Hi Slave Address
IICxHSADR
FF6X_000B
0xB
R/W
No
8
Clock Divide
IICxCLKDIV
FF6X_000C
0xC
R/W
Yes- cleared
8
Interrupt Mask
IICxINTRMSK
FF6X_000D
0xD
R/W
Yes- cleared
8
Transfer Count
IICxXFRCNT
FF6X_000E
0xE
R/W
Yes- cleared
8
Extended Control and Slave
Status
IICxXTCNTLSS
FF6X_000F
0xF
R/W
Yes- cleared
8
Direct Control
IICxDIRECTCNTL
FF6X_0010
0x10
R/W
Yes-set to ‘1’
4
LSB
MSB
X
X
X
X
X
X
X
X
R/W
X
X
0
1
1
1
1
Bit 0
Bit 15
10-bit address
Содержание CPC700
Страница 1: ...CPC700 Memory Controller and PCI Bridge User s Manual Version 1 1 Issue Date 3 22 00 Preliminary...
Страница 10: ...Table of Contents x Table of Contents...
Страница 16: ...Tables xvi List of Tables...
Страница 28: ...1 12 CPC700 User s Manual Preliminary...
Страница 72: ...3 36 Processor Interface...
Страница 132: ...4 60 Memory Controller...
Страница 184: ...5 52 PCI Interface...
Страница 194: ...6 10 Clock Power Management and Reset...
Страница 224: ...8 18 IIC...
Страница 244: ...10 10 Interrupt Controller...
Страница 246: ...I 11 2 JTAG...
Страница 250: ...12 4 Processor Local Bus PLB...
Страница 262: ...14 10 Register Summary...
Страница 267: ...CPC700 User s Manual Preliminary...