16F84A Microchip Technology, 16F84A Datasheet - Page 7

• Manufacturer Part Number: 16F84A
• Description: 18-pin Enhanced Flash/EEPROM 8-Bit Microcontroller
• Manufacturer: Microchip Technology

2.2.2
The Special Function Registers (Figure 2-1 and
Table 2-1) are used by the CPU and Peripheral
functions to control the device operation. These
registers are static RAM.
TABLE 2-1
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Ah
0Bh
Bank 1
80h
81h
82h
83h
84h
85h
86h
87h
88h
89h
0Ah
0Bh
Legend: x = unknown, u = unchanged. - = unimplemented read as '0', q = value depends on condition.
Note 1: The upper byte of the program counter is not directly accessible. PCLATH is a slave register for PC<12:8>. The contents
Bank 0
Addr
1998 Microchip Technology Inc.
2: The TO and PD status bits in the STATUS register are not affected by a MCLR reset.
3: Other (non power-up) resets include: external reset through MCLR and the Watchdog Timer Reset.
4: On any device reset, these pins are configured as inputs.
5: This is the value that will be in the port output latch.
FSR
TRISA
Name
INDF
TMR0
PCL
STATUS
FSR
PORTA
PORTB
EEDATA
EEADR
PCLATH
INTCON
INDF
OPTION_REG
PCL
STATUS
TRISB
EECON1
EECON2
PCLATH
INTCON
SPECIAL FUNCTION REGISTERS
of PCLATH can be transferred to the upper byte of the program counter, but the contents of PC<12:8> is never transferred
to PCLATH.
(4)
(5)
(2)
(2)
REGISTER FILE SUMMARY
Uses contents of FSR to address data memory (not a physical register)
8-bit real-time clock/counter
Low order 8 bits of the Program Counter (PC)
Indirect data memory address pointer 0
Unimplemented location, read as '0'
EEPROM data register
EEPROM address register
Uses contents of FSR to address data memory (not a physical register)
Low order 8 bits of Program Counter (PC)
Indirect data memory address pointer 0
PORTB data direction register
Unimplemented location, read as '0'
EEPROM control register 2 (not a physical register)
RBPU
Bit 7
RB7
GIE
GIE
IRP
IRP
—
—
—
—
—
INTEDG
Bit 6
EEIE
EEIE
RP1
RB6
RP1
—
—
—
—
—
T0CS
Bit 5
T0IE
T0IE
RP0
RB5
RP0
—
—
—
—
—
Write buffer for upper 5 bits of the PC
PORTA data direction register
Write buffer for upper 5 bits of the PC
RA4/T0CKI
T0SE
Bit 4
INTE
EEIF
INTE
RB4
TO
TO
Preliminary
WRERR
RBIE
RBIE
Bit 3
PSA
RA3
RB3
PD
PD
The special function registers can be classified into two
sets, core and peripheral. Those associated with the
core functions are described in this section. Those
related to the operation of the peripheral features are
described in the section for that specific feature.
WREN
Bit 2
T0IF
T0IF
RA2
RB2
PS2
Z
Z
(1)
(1)
Bit 1
INTF
INTF
RA1
RB1
PS1
WR
DC
DC
RB0/INT
Bit 0
RBIF
RBIF
RA0
PS0
RD
C
C
PIC16F84A
---- ----
xxxx xxxx
0000 0000
0001 1xxx
xxxx xxxx
---x xxxx
xxxx xxxx
---- ----
xxxx xxxx
xxxx xxxx
---0 0000
0000 000x
---- ----
1111 1111
0000 0000
0001 1xxx
xxxx xxxx
---1 1111
1111 1111
---- ----
---0 x000
---- ----
---0 0000
0000 000x
Power-on
Value on
Reset
DS35007A-page 7
other resets
Value on all
---- ----
uuuu uuuu
0000 0000
000q quuu
uuuu uuuu
---u uuuu
uuuu uuuu
---- ----
uuuu uuuu
uuuu uuuu
---0 0000
0000 000u
---- ----
1111 1111
0000 0000
000q quuu
uuuu uuuu
---1 1111
1111 1111
---- ----
---0 q000
---- ----
---0 0000
0000 000u
(Note3)