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Signals Description
N.U.:
Not used. By default, these signals are linked to the micro-controller,
configured at input but are not actually used.
LOCK:
Solely used on the Portable: Indicates that the synchronization with the
Base is valid. Latter indicates if the Server is at radio range. Active on
high.
RESET:
Reset hardware of the modem card. Maximum Duration: 200 ms. Active
on low.
ACK_TX:
Indicates that the buffer transmission has been executed correctly. This
signal is valid at the end of the transmission of a radio message (Active
RTS Signal) and is kept until RTS returns to inactive. Active (buffer
transmitted) on low.
xx SPI:
Signals for the Flash or the EEPROM programming of the Modem from
the host. There are three signals: Data In, Data Out and Clock.
When the host wants to read and/or modify the EEPROM, the modem
must absolutely be in reset by activating the RESET Signal.
CTS:
Clear To Send: signal into the Modem. Indicates if the Modem can send
serial data to the User (Active on low) or not (Inactive on high).
RTS:
Request To Send: signal going out of the Modem. Indicates that the user
can transmit serial data (Active on low) or not (Inactive on high). This
signal switches when the serial reception buffer's filling rate reaches a
programmable threshold (S215) or when the user finished to transmit
serial data (out on Time-Out).
TxD, RxD: Serial link signals in NRZ/TTL format. TxD is for the data going out of the
Modem while RxD is for the data coming into the Modem. Le logic '1' is
represented by high.
