The PCF8563 is a real-time clock/calendar/alarm chip with an I2C interface. This would be useful in projects where the primary microcontroller doesn’t have enough resources for an interrupt driven clock.
We demonstrate the PCF8563 using the Bus Pirate after the break. For a limited time you can get your own Bus Pirate, fully assembled and shipped worldwide, for only $30.

PCF8563 real-time clock calendar (Octopart search, $1.33). Datasheet (PDF).
The schematic above shows a bare-bones circuit for the PCF8563. It requires a simple external oscillator circuit with a 32.768khz watch crystal (Q1). The oscillator input pin needs an external…

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The Bus Pirate is a universal serial interface tool, we use it to test new chips without writing any code. It currently supports most serial protocols, including 1-Wire, I2C, SPI, JTAG, asynchronous serial, MIDI, and more. We added some other features we frequently need, like pulse-width modulation, frequency measurement, voltage measurement, bus sniffers, pull-up resistors, and switchable 3.3volt and 5volt power supplies.
The new v2 family adds USB power and connectivity to the best Bus Pirate design yet. We also reduced the part count and cost wherever possible. If you want to get your hands on some Bus Pirate…

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