RCEN fuse programmer with AT90S1200A

As you know the AT90S1200 microcontroller includes an internal RC oscillator that is disabled by default. If you want to change it (enable or disable) you must program it with parallel mode. Most programmers work with serial mode and it is not possible to program this fuse bit (RCEN). With this stand-alone programmer, you can now enable or disable the internal RC oscillator that is working at ~1MHz.

The AT90S1200 microcontroller is a low-power CMOS device that features a simple architecture suitable for a variety of applications. Its internal RC oscillator, typically operating at approximately 1 MHz, is an essential component for timing and clock generation. However, this oscillator is disabled by default, necessitating user intervention to enable it for operation.

To modify the state of the internal RC oscillator, the AT90S1200 must be programmed in parallel mode. This requirement arises because the fuse bit responsible for toggling the oscillator's state (RCEN) is not accessible through the more common serial programming mode. Serial programmers, which are widely used due to their convenience and simplicity, do not provide the capability to modify fuse bits, thus limiting their functionality in this context.

The introduction of a stand-alone programmer specifically designed for the AT90S1200 allows users to enable or disable the internal RC oscillator with ease. This programmer interfaces directly with the microcontroller's parallel programming pins, facilitating the necessary adjustments to the fuse bits. Users can configure the microcontroller to utilize the internal oscillator, thereby eliminating the need for an external clock source, which can simplify circuit design and reduce component count.

In practice, enabling the internal RC oscillator can result in a more compact and cost-effective design, particularly in battery-operated applications where minimizing power consumption is critical. Conversely, if a more precise clock is required, the ability to disable the internal oscillator and use an external clock source remains an option. The stand-alone programmer thus provides flexibility and control over the microcontroller's configuration, enhancing its usability in various electronic projects.As you know the AT90S1200 microcontroller include an internal RC oscillator that is disabled by default. If you want to change it (enable or disable) you must to program it with parallel mode. The most programmers working with serial mode and its not possible to program this fuse bit (RCEN). With this stand-alone programmer you can now enable or disable the internal RC oscillator that is working at ~1MHz.

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