Copy heximal of MCU PIC18F2455

Copy heximal of MCU PIC18F2455 and replicate the firmware to blank microcontroller PIC18F2455 which will provide the same functions as original version which can be viewed as IC clone;

Copy heximal of MCU PIC18F2455 and replicate the firmware to blank microcontroller PIC18F2455 which will provide the same functions as original version
Copy heximal of MCU PIC18F2455 and replicate the firmware to blank microcontroller PIC18F2455 which will provide the same functions as original version

For timing insensitive applications, the “RC” and “RCIO” device options offer additional cost savings. The actual oscillator frequency is a function of several factors:

operating temperature

supply voltage

values of the external resistor (REXT) and capacitor (CEXT)

Given the same device, operating voltage and temperature and component values, there will also be unit-to-unit frequency variations. These are due to factors such as:

normal manufacturing variation

difference in lead frame capacitance between package types (especially for low CEXT values)

variations within the tolerance of limits of REXT and CEXT;

In the RC Oscillator mode, the oscillator frequency divided by 4 is available on the OSC2 pin. This signal may be used for test purposes or to synchronize other logic. Figure 2-5 shows how the R/C combination is connected.

The RCIO Oscillator mode (Figure 2-6) functions like the RC mode, except that the OSC2 pin becomes an additional general purpose I/O pin. The I/O pin becomes bit 6 of PORTA (RA6).

The PLL is also available to the internal oscillator block in selected oscillator modes. In this configuration, the PLL is enabled in software and generates a clock output of up to 32 MHz.

The PIC18F2455 devices include an internal oscillator block which generates two different clock signals; either can be used as the microcontroller’s clock source. This may eliminate the need for external oscillator circuits on the OSC1 and/or OSC2 pins.

The main output (INTOSC) is an 8 MHz clock source, which can be used to directly drive the device clock. It also drives a postscaler, which can provide a range of clock frequencies from 31 kHz to 4 MHz. The INTOSC output is enabled when a clock frequency from 125 kHz to 8 MHz is selected. The other clock source is the internal RC oscillator (INTRC), which provides a nominal 31 kHz output. INTRC is enabled if it is selected as the device clock source;