
Data Sheet Revision 1.0
Page 15
OX16C954 rev B
OXFORD SEMICONDUCTOR LTD.
4.1
Pin
Further Pin Information
Description
Action when used
Action when not used
Intel Mode Bus Interface Pins
I/M#
CS0#-CS3#
Intel / Motorola Mode Tie high for Intel style bus mode
Chip selects
Connect direct to active low channel select
signals for UART channels 0-3 respectively
Leave unconnected (Internal pull-up)
n/a
Motorola Mode Bus Interface Pins
I/M#
Intel / Motorola Mode Tie low for Motorola style bus mode
n/a
Must be tied low for Motorola mode
n/a
n/a
DS#(CS0#)
A3-4 (CS1-2#)
Data Strobe
Additional
lines
Global interrupt
Connect direct to data strobe generator logic
Connect direct to channel selection logic
A[4:3] = 00 = ch. 1, 01 = ch. 2 etc.
Interrupt for all channels. Connect to an
available processor interrupt line
n/a
n/a
address
Leave unconnected
(Interrupts can not be used)
Tie high
Leave unconnected
IRQ#(INT0)
CS3#
INT1-3
Unused
Unused
Control Pins
INTSEL
Interrupt Control
Mode (used in Intel
mode only)
Tie high to keep the interrupt pins
permanently enabled.
Tie low or leave unconnected to allow
software enable/disable of the
interrupt pin.
DMA Pins
RXRDY#
DMA Control signal
output
DMA Control signal
output
Connect direct to DMA control circuitry
Leave unconnected
TXRDY#
Connect direct to DMA control circuitry
Leave unconnected
Common Channel Pins
Connect to a suitable line driver
Connect to a suitable line receiver
Connect to a suitable line driver
Connect to a suitable line receiver
Connect to a suitable line driver
Connect to a suitable line receiver
Connect to a suitable line receiver
Connect to a suitable line receiver
Connect to an available processor interrupt
line
SOUT
Serial data output
Leave unconnected
(Serial data can not be transmtted)
Leave unconnected
(Serial data can not be received)
Leave unconnected
SIN
Serial data input
RTS#
Request-To-Send
Modemsignal output
Clear-To-Send
Modemsignal input
Data-Termnal-Ready
Modemsignal output
Data-Set-Ready
Modemsignal input
Data-Carrier-Detect
Modemsignal input
Ring-Indicator
Modemsignal input
Interrupt Output
CTS#
Tie high
DTR#
Leave unconnected
DSR#
Tie high
DCD#
Tie high
RI#
Tie high
INT
Leave unconnected
(Interrupts can not be used)