Copy Secured MCU PIC18F2523 Heximal

When the IOFS bit is set, the INTOSC output is providing 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 in order to Copy Secured MCU PIC18F2523 Heximal. 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 FOSC3:FOSC0 configuration bits, then both the OSTS and IOFS bits may be set when in PRI_RUN or PRI_IDLE modes after Extract IC Code.

Copy Secured MCU PIC18F2523 Heximal

This indicates that the primary clock (INTOSC output) is generating a stable 8 MHz output. Entering another RC Power Managed mode at the same frequency would clear the OSTS bit.

Note 1: Caution should be used when modifying a single IRCF bit. If VDD is less than 3V, it is possible to select a higher clock speed than is supported by the low VDD. Improper device operation may result if the VDD/FOSC specifications are violated before Read MCU AT89C51AC2 Software.

2: Executing a SLEEP instruction does not 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.

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 after the operation of Read MCU AT89C51RB2 Eprom.

In the Run modes, clocks to both the core and peripherals are active. The difference between these modes is the clock source. 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 23.3 “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 2.7.1 “Oscillator Control Register”) when Unlock microcontroller.