
S3C828B/F828B/C8289/F8289/C8285/F8285
ADDRESS SPACES
2-9
REGISTER PAGE POINTER (PP)
The S3C8-series architecture supports the logical expansion of the physical 256-byte internal register file (using
an 8-bit data bus) into as many as 16 separately addressable register pages. Page addressing is controlled by
the register page pointer (PP, DFH). In the S3C828B/C8289/C8285 microcontroller, a paged register file
expansion is implemented for LCD data registers, and the register page pointer must be changed to address
other pages.
After a reset, the page pointer's source value (lower nibble) and the destination value (upper nibble) are always
"0000", automatically selecting page 0 as the source and destination page for register addressing.
Register Page Pointer (PP)
DFH ,Set 1, R/W
LSB
MSB
.7
.6
.5
.4
.3
.2
.1
.0
Destination register page selection bits:
0000
Destination: Page 0
0001
Destination: Page 1
0010
Destination: Page 2 (Not used for the S3C8285)
0011
Destination: Page 3 (Not used for the S3C8285)
0100
Destination: Page 4 (Not used for the S3C8289/5)
0101
Destination: Page 5 (Not used for the S3C8289/5)
0110
Destination: Page 6 (Not used for the S3C8289/5)
0111
Destination: Page 7 (Not used for the S3C8289/5)
1000
Destination: Page 8 (Not used for the S3C8289/5)
1001
Destination: Page 9 (Not used for the S3C8289/5)
1111
Destination: Page 15
Others Not used for the S3C828B/9/5
Source register page selection bits:
0000
Source: page 0
0001
Source: page 1
0010
Source: page 2 (not used for the S3C8285)
0011
Source: page 3 (not used for the S3C8285)
0100
Source: page 4 (not used for the S3C8289/5)
0101
Source: page 5 (not used for the S3C8289/5)
0110
Source: page 6 (not used for the S3C8289/5)
0111
Source: page 7 (not used for the S3C8289/5)
1000
Source: page 8 (not used for the S3C8289/5)
1001
Source: page 9 (not used for the S3C8289/5)
1111
Source: page 15
Others Not used for the S3C828B/9/5
NOTES:
1. In the S3C828B microcontroller, the internal register file is configured as eleven pages (Pages 0-9, 15).
The pages 0-9 are used for general purpose register file.
2. In the S3C8289 microcontroller, the internal register file is configured as five pages (Pages 0-3, 15).
3. In the S3C8285 microcontroller, the internal register file is configured as three pages (Pages 0-1, 15)
The page 0-1 is used for general purpose register file.
4. The page 15 of S3C828B/9/5 is used for LCD data register or general purpose regiser.
Figure 2-6. Register Page Pointer (PP)