PIC16LC774-I/P View Datasheet(PDF) - Microchip Technology
Part Name
Description
Manufacturer
PIC16LC774-I/P Datasheet PDF : 202 Pages
| |||
PIC16C77X
12.3 Reset
The PIC16C77X devices have several different resets.
These resets are grouped into two classifications;
power-up and non-power-up. The power-up type resets
are the power-on and brown-out resets which assume
the device VDD was below its normal operating range
for the device’s configuration. The non-power up type
resets assume normal operating limits were main-
tained before/during and after the reset.
• Power-on Reset (POR)
• Brown-out Reset (BOR)
• MCLR reset during normal operation
• MCLR reset during SLEEP
• WDT Reset (during normal operation)
Some registers are not affected in any reset condition.
Their status is unknown on a power-up reset and
unchanged in any other reset. Most other registers are
placed into an initialized state upon reset, however they
are not affected by a WDT reset during sleep because
this is considered a WDT Wakeup, which is viewed as
the resumption of normal operation.
Several status bits have been provided to indicate
which reset occurred (see Table 12-4). See Table 12-6
for a full description of reset states of all registers.
A simplified block diagram of the on-chip reset circuit is
shown in Figure 12-5.
These devices have a MCLR noise filter in the MCLR
reset path. The filter will detect and ignore small pulses.
It should be noted that a WDT Reset does not drive
MCLR pin low.
FIGURE 12-5: SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
External
Reset
MCLR
VDD
SLEEP
WDT WDT
Module Time-out
Reset
VDD rise
detect
Power-on Reset
Brown-out
Reset BODEN
OSC1
OST/PWRT
OST
10-bit Ripple counter
(1)
On-chip
RC OSC
PWRT
10-bit Ripple counter
S
Chip_Reset
R
Q
Enable PWRT
Enable OST
Note 1: This is a separate oscillator from the RC oscillator of the CLKIN pin.
1999-2013 Microchip Technology Inc.
Advance Information
DS30275B-page 131
Share Link: 