PIC18F4580T-I/PT Microchip Technology, PIC18F4580T-I/PT Datasheet - Page 40

• Manufacturer Part Number: PIC18F4580T-I/PT
• Description: IC PIC MCU FLASH 16KX16 44TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F4580T-I/PT

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: CAN, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, HLVD, POR, PWM, WDT
• Number Of I /o: 36
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 1.5K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 11x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

PIC18F2480/2580/4480/4580
4.1.3
The length of the transition between clock sources is
the sum of two cycles of the old clock source and three
to four cycles of the new clock source. This formula
assumes that the new clock source is stable.
Three bits indicate the current clock source and its
status. They are:
• OSTS (OSCCON<3>)
• IOFS (OSCCON<2>)
• T1RUN (T1CON<6>)
In general, only one of these bits will be set while in a
given power-managed mode. When the OSTS bit is
set, the primary clock is providing the device clock.
When the IOFS bit is set, the INTOSC output is provid-
ing a stable 8 MHz clock source to a divider that
actually drives the device clock. When the T1RUN bit is
set, the Timer1 oscillator is providing the clock. If none
of these bits are set, then either the INTRC clock
source is clocking the device, or the INTOSC source is
not yet stable.
If the internal oscillator block is configured as the
primary clock source by the FOSC<3:0> Configuration
bits, then both the OSTS and IOFS bits may be set
when in PRI_RUN or PRI_IDLE modes. This indicates
that the primary clock (INTOSC output) is generating a
stable
power-managed mode at the same frequency would
clear the OSTS bit.
4.1.4
The power-managed mode that is invoked with the
SLEEP instruction is determined by the setting of the
IDLEN bit at the time the instruction is executed. If
another SLEEP instruction is executed, the device will
enter the power-managed mode specified by IDLEN at
that time. If IDLEN has changed, the device will enter the
new power-managed mode specified by the new setting.
DS39637D-page 40
Note 1: Caution should be used when modifying a
2: Executing a SLEEP instruction does not
8 MHz
CLOCK TRANSITIONS AND STATUS
INDICATORS
MULTIPLE SLEEP COMMANDS
single IRCF bit. If V
possible to select a higher clock speed
than is supported by the low V
Improper device operation may result if
the V
necessarily place the device into Sleep
mode. It acts as the trigger to place the
controller into either the Sleep mode, or
one of the Idle modes, depending on the
setting of the IDLEN bit.
DD
output.
/F
OSC
specifications are violated.
Entering
DD
is less than 3V, it is
another
DD
RC
.
Upon resuming normal operation after waking form
Sleep or Idle, the internal state machines require at
least one T
can be executed. If two back-to-back SLEEP instruc-
tions need to be executed, the process shown in
Example 4-1 should be used.
EXAMPLE 4-1:
4.2
In the Run modes, clocks to both the core and
peripherals are active. The difference between these
modes is the clock source.
4.2.1
The PRI_RUN mode is the normal, full-power execution
mode of the microcontroller. This is also the default
mode upon a device Reset, unless Two-Speed Start-up
is enabled (see Section 25.3 “Two-Speed Start-up” for
details). In this mode, the OSTS bit is set. The IOFS bit
may be set if the internal oscillator block is the primary
clock source (see Section 3.7.1 “Oscillator Control
Register”).
4.2.2
The SEC_RUN mode is the compatible mode to the
“clock switching” feature offered in other PIC18
devices. In this mode, the CPU and peripherals are
clocked from the Timer1 oscillator. This gives users the
option of lower power consumption while still using a
high accuracy clock source.
SEC_RUN mode is entered by setting the SCS<1:0>
bits to ‘01’. The device clock source is switched to the
Timer1 oscillator (see Figure 4-1), the primary oscilla-
tor is shut down, the T1RUN bit (T1CON<6>) is set and
the OSTS bit is cleared.
SLEEP
NOP
executing another SLEEP instruction
SLEEP
Note:
Run Modes
CY
; Wait at least 1 Tcy before
PRI_RUN MODE
SEC_RUN MODE
The Timer1 oscillator should already be
running prior to entering SEC_RUN mode.
If the T1OSCEN bit is not set when the
SCS<1:0> bits are set to ‘01’, entry to
SEC_RUN mode will not occur. If the
Timer1 oscillator is enabled but not yet
running, device clocks will be delayed until
the oscillator has started. In such situa-
tions, initial oscillator operation is far from
stable and unpredictable operation may
result.
delay before another SLEEP instruction
EXECUTING
BACK-TO-BACK SLEEP
INSTRUCTIONS
© 2009 Microchip Technology Inc.