Phytec phyCORE-LPC2292/94, Hardware Manual

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Serial Interfaces
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PHYTEC Messtechnik GmbH 2006 L-658e_5
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6 Serial Interfaces
6.1 RS-232 Interfaces
One RS-232 transceiver is populating the phyCORE-LPC2292/94 at
U200. This device converts the signal levels for:
•
P01/RxD0 and P00/TxD0 (frist serial interface)
•
P09/RxD1 and P08/TxD1 (second serial interface)
The ports listed above can also be used alternatively as standard I/Os,
as interface signals with TTL-level or in their alternative function on
the phyCORE-connector X700. For this Jumpers J201 and J203 as
well as J200 and J202 must be closed at position 2 + 3.
All RS-232 interfaces enable connection of the module to a COM port
on a host-PC. In this instance the RxD line of the transceiver is
connected to the TxD line of the COM port; while the TxD line is
connected to the RxD line of the COM port. The Ground potential of
the phyCORE-LPC2292/94 circuitry needs to be connected to the
applicable Ground pin on the COM port as well.
One of the microcontroller’s on-chip UARTs (UART0) does not
support handshake signal communication. However, depending on
user needs, handshake communication can be software emulated using
port pins on the microcontroller. The controllers second UART
(UART1) supports standard modem signals. However, these signals
are not converted to RS-232 signal level on the
phyCORE-LPC2292/94. All modem signals are routed to the
phyCORE-connector at X700. In order to support handshake
communication with RS-232 signal level an external RS-232
transceiver is required. The applicable circuirty needs to be added by
the user.