Intel PXA255 manual Synchronous Serial Protocol Controller Sspc, Gpio, UARTs

Introduction

1.2.10Synchronous Serial Protocol Controller (SSPC)

The SSP Port provides a full-duplex synchronous serial interface that operates at bit rates from

7.2 kHz to 1.84 MHz. It supports National Semiconductor’s Microwire*, Texas Instruments’ Synchronous Serial Protocol*, and Motorola’s Serial Peripheral Interface*. The SSPC has FIFOs with DMA access to memory.

1.2.11Inter-Integrated Circuit (I2C) Bus Interface Unit

The I2C Bus Interface Unit provides a general purpose 2-pin serial communication port.The interface uses one pin for data and address and a second pin for clocking.

1.2.12GPIO

Each GPIO pin can be individually programmed as an output or an input. Inputs can cause interrupts on rising or falling edges. Primary GPIO pins are not shared with peripherals while secondary GPIO pins have alternate functions which can be mapped to the peripherals.

1.2.13UARTs

The processor provides three Universal Asynchronous Receiver/Transmitters. Each UART can be used as a slow infrared (SIR) transmitter/receiver based on the Infrared Data Association Serial Infrared (SIR) Physical Layer Link Specification.

1.2.13.1Full Function UART (FFUART)

The FFUART baud rate is programmable up to 230 Kbps. The FFUART provides a complete set of modem control pins: nCTS, nRTS, nDSR, nDTR, nRI, and nDCD. It has FIFOs with DMA access to or from memory.

1.2.13.2Bluetooth UART (BTUART)

The BTUART baud rate is programmable up to 921 Kbps. The BTUART provides a partial set of modem control pins: nCTS and nRTS. Other modem control pins can be implemented via GPIOs. The BTUART has FIFOs with DMA access to or from memory.

1.2.13.3Standard UART (STUART)

The STUART baud rate is programmable up to 230 Kbps. The STUART does not provide any modem control pins. The modem control pins can be implemented via GPIOs. The STUART has FIFOs with DMA access to or from memory.

The STUART’s transmit and receive pins are multiplexed with the Fast Infrared Communication Port.

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