Microchip Technology IC MCU FLASH 4K PIC16LF88-I/P DIP-18 MCP PIC16LF88-I/P Datenbogen
Produktcode
PIC16LF88-I/P
2002-2013 Microchip Technology Inc.
DS30487D-page 11
PIC16F87/88
2.0
MEMORY ORGANIZATION
There are two memory blocks in the PIC16F87/88
devices. These are the program memory and the data
memory. Each block has its own bus, so access to each
block can occur during the same oscillator cycle.
devices. These are the program memory and the data
memory. Each block has its own bus, so access to each
block can occur during the same oscillator cycle.
The data memory can be further broken down into the
general purpose RAM and the Special Function
Registers (SFRs). The operation of the SFRs that
control the “core” are described here. The SFRs used
to control the peripheral modules are described in the
section discussing each individual peripheral module.
general purpose RAM and the Special Function
Registers (SFRs). The operation of the SFRs that
control the “core” are described here. The SFRs used
to control the peripheral modules are described in the
section discussing each individual peripheral module.
The data memory area also contains the data EEPROM
memory. This memory is not directly mapped into the
data memory but is indirectly mapped. That is, an indi-
rect address pointer specifies the address of the data
EEPROM memory to read/write. The PIC16F87/88
device’s 256 bytes of data EEPROM memory have the
address range of 00h-FFh. More details on the
EEPROM memory can be found in Section 3.0 “Data
EEPROM and Flash Program Memory”.
memory. This memory is not directly mapped into the
data memory but is indirectly mapped. That is, an indi-
rect address pointer specifies the address of the data
EEPROM memory to read/write. The PIC16F87/88
device’s 256 bytes of data EEPROM memory have the
address range of 00h-FFh. More details on the
EEPROM memory can be found in Section 3.0 “Data
EEPROM and Flash Program Memory”.
Additional information on device memory may be found
in the “PIC
in the “PIC
®
Mid-Range MCU Family Reference Man-
ual” (DS33023).
2.1
Program Memory Organization
The PIC16F87/88 devices have a 13-bit program coun-
ter capable of addressing an 8K x 14 program memory
space. For the PIC16F87/88, the first 4K x 14 (0000h-
0FFFh) is physically implemented (see Figure 2-1).
Accessing a location above the physically implemented
address will cause a wraparound. For example, the
same instruction will be accessed at locations 020h,
420h, 820h, C20h, 1020h, 1420h, 1820h and 1C20h.
ter capable of addressing an 8K x 14 program memory
space. For the PIC16F87/88, the first 4K x 14 (0000h-
0FFFh) is physically implemented (see Figure 2-1).
Accessing a location above the physically implemented
address will cause a wraparound. For example, the
same instruction will be accessed at locations 020h,
420h, 820h, C20h, 1020h, 1420h, 1820h and 1C20h.
The Reset vector is at 0000h and the interrupt vector is
at 0004h.
at 0004h.
FIGURE 2-1:
PROGRAM MEMORY MAP
AND STACK: PIC16F87/88
AND STACK: PIC16F87/88
2.2
Data Memory Organization
The data memory is partitioned into multiple banks that
contain the General Purpose Registers and the Special
Function Registers. Bits RP1 (STATUS<6>) and RP0
(STATUS<5>) are the bank select bits.
contain the General Purpose Registers and the Special
Function Registers. Bits RP1 (STATUS<6>) and RP0
(STATUS<5>) are the bank select bits.
Each bank extends up to 7Fh (128 bytes). The lower
locations of each bank are reserved for the Special
Function Registers. Above the Special Function Regis-
ters are General Purpose Registers, implemented as
static RAM. All implemented banks contain SFRs.
Some “high use” SFRs from one bank may be mirrored
in another bank for code reduction and quicker access
(e.g., the STATUS register is in Banks 0-3).
locations of each bank are reserved for the Special
Function Registers. Above the Special Function Regis-
ters are General Purpose Registers, implemented as
static RAM. All implemented banks contain SFRs.
Some “high use” SFRs from one bank may be mirrored
in another bank for code reduction and quicker access
(e.g., the STATUS register is in Banks 0-3).
RP1:RP0
Bank
00
0
01
1
10
2
11
3
Note:
EEPROM data memory description can be
found in Section 3.0 “Data EEPROM and
Flash Program Memory” of this data
sheet.
found in Section 3.0 “Data EEPROM and
Flash Program Memory” of this data
sheet.
PC<12:0>
13
0000h
0004h
0005h
0005h
Stack Level 1
Stack Level 8
Reset Vector
Interrupt Vector
On-Chip
CALL, RETURN
RETFIE, RETLW
RETFIE, RETLW
1FFFh
Stack Level 2
Program
Memory
Page 0
07FFh
Wraps to
0000h-03FFh
Page 1
0FFFh
1000h
1000h
0800h