8-bit microcontroller with accelerated two-clock 80C51 core
8.19.9 CCU interrupts
There are seven interrupt sources on the CCU which share a common interrupt vector.
Fig 13. Capture/compare unit interrupts
The P89LPC933/934/935/936 has an enhanced UART that is compatible with the
conventional 80C51 UART except that Timer 2 overflow cannot be used as a baud rate
source. The P89LPC933/934/935/936 does include an independent baud rate generator.
The baud rate can be selected from the oscillator (divided by a constant), Timer 1
overflow, or the independent baud rate generator. In addition to the baud rate generation,
enhancements over the standard 80C51 UART include Framing Error detection,
automatic address recognition, selectable double buffering and several interrupt options.
The UART can be operated in four modes: shift register, 8-bit UART, 9-bit UART, and CPU
clock⁄32 or CPU clock⁄16.
8.20.1 Mode 0
Serial data enters and exits through RXD. TXD outputs the shift clock. 8 bits are
transmitted or received, LSB first. The baud rate is fixed at 1⁄16 of the CPU clock
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 8 — 12 January 2011
© NXP B.V. 2011. All rights reserved.
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