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Hardware Description
Copyright © ARM Limited 2000. All rights reserved.
3-27
Maxim MAX3225 transceivers provide signal level conversion for the RS232
interfaces. These feature:
•
a guaranteed maximum data rate of 1Mbps (which exceeds the 230.4kbps upper
limit of the UART)
•
an automatic power-down mode. This is entered when a cable is not attached, or
when transmitters are inactive for more than 30 seconds. The power-down mode
can be overridden by asserting the
PLD_COM1_EN
signal.
The MAX3225 is powered from the non-sw3V rail.
COM1_RDY
COM1
transceiver
This signal is monitored by the PLD and controls the state of the
COM1_READY bit in the Peripheral Control Register. Read this
bit to determine if the serial port is ready to transmit.
COM1_SENSE
COM1 transceiver
This signal is monitored by the PLD and controls the state of the
COM1_SENSE bit in the Peripheral Control Register. Read this bit
to determine if a cable is plugged into the socket.
COM2_RDY
COM1
transceiver
This signal is monitored by the PLD and controls the state of the
COM2_READY bit in the Peripheral Control Register. Read this
bit to determine if the serial port is ready to transmit.
COM2_SENSE
COM1 transceiver
This signal is monitored by the PLD and controls the state of the
COM2_SENSE bit in the Peripheral Control Register. Read this bit
to determine if a cable is plugged into the socket.
PLD_COM1_EN
System controller PLD
This signal is used to enable/disable the COM1 transceiver. It is
controlled by the COM1_EN bit in the peripheral control register
(see COM1 enable register on page 4-17).
PLD_COM2_EN
System controller PLD
This signal is used to enable/disable the COM2 transceiver. It is
controlled by the COM2_EN bit in the peripheral control register
(see COM2 enable register on page 4-17).
Table 3-12 COMs channel host signals (continued)
Signal
Source
Function
Summary of Contents for Prospector P1100
Page 1: ...ARM DUI 0122A Prospector P1100 User Guide ...
Page 4: ...iv Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...
Page 86: ...Hardware Description 3 54 Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...
Page 140: ...Connector reference A 18 Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...