Emerson MVME4100, Инструкция по установке и эксплуатации

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Functional Description
MVME4100 Single Board Computer Installation and Use (6806800H18D )
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4.8.2 NVRAM
The MVME4100 includes one Freescale 512 MB MRAM device connected to the MPC8548E
device control bus to provide a non-volatile memory that has unlimited writes, fast access and
long term data retention without power. The MRAM device selected is also an extended
temperature device with an operating range from -40 °C to 105 °C/-40 °F to +221 °F. The
MRAM is organized as 256 K by 16. Refer to the data sheet for additional information.
4.8.3 Quad UART (QUART)
The MVME4100 contains one Quad UART device connected to the MPC8548E device control
bus to provide additional asynchronous serial ports. The Quad UART provides four
asynchronous serial ports which are routed to the P2 connector. The TTL-level signals of RX, TX,
CTS, and RTS from each port are routed through on-board RS-232 drivers and receivers to the
P2 connector where the signals can be picked up by a transition module. The reference clock
frequency for the QUART is 1.8432 MHz. All UART ports are capable of signaling at up to
115 Kbaud. Refer to the ST16C554D data sheet for additional details and/or programming
information.
4.8.4 Control and Timers PLD
The MVME4100 Control and Timers PLD resides on the local bus. The Control and Timers PLD
provides the following functions on the board:
z
Local bus address latch
z
Chip selects for flash banks, MRAM, and Quad UART
z
System control and status registers
z
Four 32-bit tick timers
z
Watch Dog Timer
z
RTC 1 MHz reference clock