AN1177 STMicroelectronics, AN1177 Datasheet - Page 20

• Manufacturer Part Number: AN1177
• Description: P51XA-PSD8XX DESIGN GUIDE
• Manufacturer: STMicroelectronics

AN1177 - APPLICATION NOTE
Figure 7. Memory Map After Moving the Main Flash Memory to Program Space
Memory Map Configuration After Setting the swap bit. Next, we want to swap main and secondary
Flash memory and transfer execution to main Flash memory segment fs7. To do so, the “swap” bit must
be set to HI to re-map the Flash memory boot segments csboot0/csboot1 out of the MCU boot area and
replace it with main Flash memory segment fs7, as shown in Figure 8. So that no program continuity is
lost, the instruction that sets the “swap” bit is executed from csboot0 and the next contiguous instruction
must be in fs7. For example, if the instruction that executes the swap is at location 1000h in csboot0, then
fs7 must contain the next instruction to be executed at location 1002h.
20/26
Not to
Scale
Execute
Here
from
1:C000
F:FFFF
2:FFFF
2:C000
2:8000
2:4000
2:0000
1:8000
1:4000
1:0000
0:8000
0:6000
0:4000
0:2000
0:0000
Optional Boot Flash/EEPROM (csboot3/ees3--8 Kbytes)
Optional Boot Flash/EEPROM (csboot2/ees2--8 Kbytes)
Optional Boot Flash/EEPROM (csboot1/ees1--8 Kbytes)
Optional Boot Flash/EEPROM (csboot0/ees0--8 Kbytes)
Main Flash Memory FS6
Main Flash Memory FS7
Main Flash Memory FS5
Main Flash Memory FS3
Main Flash Memory FS1
Main Flash Memory FS0
Main Flash Memory FS4
Main Flash Memory FS2
Program Space
16 KBytes FLASH
16 KBytes FLASH
16 KBytes FLASH
16 KBytes FLASH
16 KBytes FLASH
16 KBytes FLASH
16 KBytes FLASH
16 KBytes FLASH
13 x 64 KBytes
Unmapped
Unmapped
32 KBytes
VM Register = 06h
Not to
Not to
swap = 0
Scale
Scale
F:FFFF
2:FFFF
0:1900
0:1000
0:1800
0:0000
PSD Control Register (CSIOP)
80C51XA On-Chip RAM
Optional SRAM (RS0)
256 Bytes to 1 KByte
3 to 3.75 KBytes
13 x 64 KBytes
Data Space
Unmapped
185.75 KBytes
Unmapped
Unmapped
256 Bytes
2 KBytes
AI03335B