Datasheet

PIC17C4X
DS30412C-page 30  1996 Microchip Technology Inc.
TABLE 6-1: MODE MEMORY ACCESS
Operating
Mode
Internal
Program
Memory
Configuration Bits,
Test Memory,
Boot ROM
Microprocessor No Access No Access
Microcontroller Access Access
Extended
Microcontroller
Access No Access
Protected
Microcontroller
Access Access
The PIC17C4X can operate in modes where the pro-
gram memory is off-chip. They are the microprocessor
and extended microcontroller modes. The micropro-
cessor mode is the default for an unprogrammed
device.
Regardless of the processor mode, data memory is
always on-chip.
FIGURE 6-2: MEMORY MAP IN DIFFERENT MODES
Microprocessor
Mode
0000h
FFFFh
External
Program
Memory
External
Program
Memory
0800h
FFFFh
0000h
07FFh
On-chip
Program
Memory
Extended
Microcontroller
Mode
Microcontroller
Modes
0000h
07FFh
0800h
FE00h
FFFFh
OFF-CHIP ON-CHIP OFF-CHIP ON-CHIP OFF-CHIP ON-CHIP
00h
FFh
00h
FFh
00h
FFh
OFF-CHIP ON-CHIP OFF-CHIP ON-CHIP OFF-CHIP ON-CHIP
PROGRAM SPACEDATA SPACE
Config. Bits
Test Memory
Boot ROM
PIC17C42,
0000h
FFFFh
External
Program
Memory
External
Program
Memory
1000h/
FFFFh
0000h
0000h
0FFFh/1FFFh
1000h/2000h
FE00h
FFFFh
OFF-CHIP ON-CHIP OFF-CHIP ON-CHIP OFF-CHIP ON-CHIP
Config. Bits
Test Memory
Boot ROM
PROGRAM SPACEDATA SPACE
00h
FFh 1FFh
120h
OFF-CHIP ON-CHIP
00h
FFh 1FFh
120h
OFF-CHIP ON-CHIP
00h
FFh 1FFh
120h
OFF-CHIP ON-CHIP
0FFFh/1FFFh
2000h
PIC17CR42,
PIC17C42A
PIC17C43,
PIC17CR43,
PIC17C44
On-chip
Program
Memory
On-chip
Program
Memory
On-chip
Program
Memory