Nokia 9000i Service Manual page 157

After Sales
Technical Documentation
SIRU
Introduction
IrDA transceiver and RS232 buffer are located to this module. Infrared
interface conforms to the Infrared Data Association Serial Interface (SIR)
Physical Layer LInk Specification.
SIRU functions:
– external interface signalling (IrDA and RS232)
Technical Description
Table 26. External Signals and Connections, Inputs
Signal Name
VSYS System voltage 3.3V
TXD External serial data from 9000
RSTXD Serial data from PROCU module
RSENX RS buffer enable
RSSHDX RS buffer shutdown
IRSHD IR tranceiver shutdown
Note 1. SC = System Connector
Table 27. External Signals and Connections, Outputs
Signal Name
RXD External serial data to 9000
RSRXD Serial data to PDA module
Note 1. SC = System Connector
Main components
– IR tranceiver
– Temic IrDA SIR integrated transceiver TFDS3000
– Shutdown pin
– RS 232 buffer
– MAX3222CAP transceiver from Maxim
– Two transmitters, two receivers
– Generates EIA/TIA–232 compatible signal levels
Original, 08/96
Signal description
Signal description
RAE/RAK–1N
PDA Hardware
From (1)
PDAPWRU
SC /
SYSTXD
PROCU
PROCU
PROCU
PROCU
To (1)
SC /
SYSRXD
PROCU
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