PIC18F4539 Datasheet, PDF (52/322 Pages) Microchip Technology – Enhanced FLASH Microcontrollers with Single Phase Induction Motor Control Kernel

PIC18FXX39
4.14 RCON Register
The Reset Control (RCON) register contains flag bits
that allow differentiation between the sources of a
device RESET. These flags include the TO, PD, POR,
BOR and RI bits. This register is readable and writable.
For PIC18FXX39 devices, the IPEN bit must always be
set (= 1) for the ProMPT kernel to function correctly.
Refer to Section 8.0 (page 69) for a more detailed
discussion.
REGISTER 4-3: RCON REGISTER
R/W-0
U-0
U-0
IPEN
—
—
bit 7
Note 1: If the BOREN configuration bit is set
(Brown-out Reset enabled), the BOR bit is
‘1’ on a Power-on Reset. After a Brown-
out Reset has occurred, the BOR bit will
be cleared, and must be set by firmware to
indicate the occurrence of the next
Brown-out Reset.
2: It is recommended that the POR bit be set
after a Power-on Reset has been
detected, so that subsequent Power-on
Resets may be detected.
R/W-1
R-1
RI
TO
R-1
R/W-0 R/W-0
PD
POR
BOR
bit 0
bit 7
bit 6-5
bit 4
bit 3
bit 2
bit 1
bit 0
IPEN: Interrupt Priority Enable bit
Always maintain this bit set for proper operation of ProMPT kernel.
Unimplemented: Read as '0'
RI: RESET Instruction Flag bit
1 = The RESET instruction was not executed
0 = The RESET instruction was executed causing a device RESET
(must be set in software after a Brown-out Reset occurs)
TO: Watchdog Time-out Flag bit
1 = After power-up, CLRWDT instruction, or SLEEP instruction
0 = A WDT time-out occurred
PD: Power-down Detection Flag bit
1 = After power-up or by the CLRWDT instruction
0 = By execution of the SLEEP instruction
POR: Power-on Reset Status bit
1 = A Power-on Reset has not occurred
0 = A Power-on Reset occurred
(must be set in software after a Power-on Reset occurs)
BOR: Brown-out Reset Status bit
1 = A Brown-out Reset has not occurred
0 = A Brown-out Reset occurred
(must be set in software after a Brown-out Reset occurs)
Legend:
R = Readable bit
- n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared x = Bit is unknown
DS30485A-page 50
Preliminary
 2002 Microchip Technology Inc.