Information

Overview
MPC8308 PowerQUICC II Pro Processor Reference Manual, Rev. 1
1-16 Freescale Semiconductor
1.2.11 Dual Universal Asynchronous Receiver/Transmitter (DUART)
The device includes a Dual universal Asynchronous Reciever/Transmitter (DUART) intended for use in
maintenance, bring up, and debug systems. The device provides a standard two-wire data (TXD and RXD)
for each port. The DUART is a slave interface. An interrupt is provided to the interrupt controller.
Interrupts are generated for transmit, receive, and line status.
The DUART supports full-duplex operation. It is compatible with the PC16450 and PC16550
programming models. The transmitter and receiver both support 16-byte FIFOs.
Software programmable baud rate generators divide the system clock to generate a 16x clock. Serial
interface data formats (data length, parity, 1/1.5/2 STOP bit, baud rate) are also software selectable.
The DUART includes the following features:
• Full-duplex operation
• Programming model compatible with the original PC16450 UART and the PC16550D (an
improved version of the PC16450 that also operates in FIFO mode)
• PC16450 register reset values
• FIFO mode for both transmitter and receiver, providing 16-byte FIFOs
• Serial data encapsulation and decapsulation with standard asynchronous communication bits
(START, STOP, and parity)
• Maskable transmit, receive, and line status interrupts
• Software-programmable baud rate generators that divide the system clock by 1 to (2
16
– 1) and
generate a 16x clock for the transmitter and receiver engines
• Software-selectable serial-interface data format (data length, parity, 1/1.5/2 STOP bit, baud rate)
• Line status registers
• Line-break detection and generation
• Internal diagnostic support, local loopback, and break functions
• Prioritized interrupt reporting
• Overrun, parity, and framing error detection
1.2.12 Enhanced Secure Digital Host Controller (eSDHC)
The enhanced secure digital host controller (eSDHC) provides an interface between the host system and
these types of memory cards:
• MultiMediaCard (MMC)
MMC is a universal low-cost data storage and communication medium designed to cover a wide
area of applications including mobile video and gaming, which are available from either pre-loaded
MMC cards or downloadable from cellular phones, WLAN, or other wireless networks.
• Secure digital (SD) card
The secure digital (SD) card is an evolution of old MMC technology. It is specifically designed to
meet the security, capacity, performance, and environment requirements inherent in the emerging