
Socket iChip Carrier Board
iChip & iChip LAN Datasheet 8-4
transmitter holds the data in the serial port transmit register. The value of ~CTSM is
checked only at the beginning of the transmission of the frame.
~RTSM,
Ready To Send Modem (TTL Active Low, EIA-232 Active High),Output
This pin provides the Ready to Send signal for asynchronous serial port when the
hardware flow control is enabled for the port. The ~RTSM signal is asserted when the
associated serial port transmit register contains data that has not been transmitted.
~DTRM,
Data Terminal Ready Modem (TTL Active Low, EIA-232 Active High), Output.
When flow control is enabled, this pin is Channel Data Terminal Ready Output.
~DSRM,
Data Set Ready Modem (TTL Active Low, EIA-232 Active High), Input.
When Flow control is enabled, this pin is Data Set Ready input.
~RIM,
Ring Indicate Modem (TTL Active Low, EIA-232 Active High), Input.
~RIM input ON (low) indicates the presence of an ON segment of a ring signal on the
telephone line (This signal is ignored by the socket iChip).
~CDM,
Carrier Detect Modem (TTL Active Low, EIA-232 Active High), Input.
This pin is the Carrier Detect Input from the modem.
8.2.2 Host Interface Signals
CO561AD-CT/R Interfaces to a Host CPU via asynchronous serial interface with TTL
(T) or EIA-232 (R) signal levels.
~ TXDH/TXD232
Transmit Data Host (output, asynchronous)
This pin supplies asynchronous serial transmit data to the system from serial port.
~RXDH/RXD232
Receive Data Host (input, asynchronous)
This pin supplies asynchronous serial receive data from the system to asynchronous serial
port.
~CTSH/CTS232
Clear-to-Send Host (input, asynchronous)
This pin provides the Clear to Send signal for asynchronous serial port 1 when the
hardware flow control is enabled for the port. The ~CTSH signal gates the transmission
of data from the associated serial port transmit register. When ~CTSH is asserted, the
transmitter begins transmission of a frame of data, if any is available. If ~CTSH is de-
asserted, the transmitter holds the data in the serial port transmit register. The value of
~CTSH is checked only at the beginning of the transmission of the frame.