Peripheral Simulation

For Dallas Semiconductor DS89C440 — Ring Oscillator

Simulation support for this peripheral or feature is comprised of:

• Accurate simulation of special on-chip features.
• VTREGs (Virtual Target Registers) which support I/O with the peripheral.

These simulation capabilities are described below.

Ring Oscillator

The Ring Oscillator is an internal 2-4 MHz clock source used to quickly resume operation without waiting for an external clock source to stabilize. Without the Ring Oscillator, a crystal warm-up period of 65,536 clock cycles is required before program execution can resume. The Ring Oscillator feature allows the program to resume immediately using this internal clock until the crystal has completed its warm-up cycle.

RING VTREG
Data Type: unsigned long

The RING VTREG contains the frequency of the internal ring oscillator (in Hertz) which may be used to drive the microcontroller. You may change the value of RING using the command window. For example:

RING=5000000

You may also output the current value of RING using the following:

RING