The MAX6952 is an SPI based 5x7 dot matrix LED display driver that can drive up to 4 monochrome displays or 2 dual-colour displays.
The MAX232 is a very well known chip that converts TTL USART signals (such as the ones on the PIC) to RS232 level signals (on the PC).
The DS3234 is a precision real time clock with integrated crystal and 256 bytes of SRAM.
The MAX5402 is a 256 step digital potentiometer.
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