ML674000
Oki Semiconductor
Primary/
Pin Name
I/O
Description
Logic
Secondary
DMA control signals
Ch 0 DMA request signal, used when DMA controller configured for DREQ
type
DREQ0
I
Secondary
Positive
Ch 0 DREQ signal clear request. The DMA device responds to this output
by negating DREQ.
DREQCLR0
TCOUT0
DREQ1
O
O
I
Secondary
Secondary
Secondary
Positive
Positive
Positive
Indicates to Ch 0 DMA device that last transfer has started
Ch 1 DMA request signal, used when DMA controller configured for DREQ
type
Ch 1 DREQ signal clear request. The DMA device responds to this output
by negating DREQ.
DREQCLR1
TCOUT1
O
O
Secondary
Secondary
Positive
Positive
Indicates to Ch 1 DMA device that last transfer has started
Serial IO Interface
STXD
SRXD
UART
SIN
O
SIO transmit signal
SIO receive signal
Secondary
Secondary
Positive
Positive
I
I
Serial data input
Serial data output
Secondary
Secondary
Positive
Positive
SOUT
O
Clear To Send.
Indicates that modem or data set is ready to transfer data.
Bit 4 in modem status register reflects this input.
CTS
DSR
DCD
DTR
I
I
Secondary
Secondary
Secondary
Secondary
Negative
Negative
Negative
Negative
Data Set Ready.
Indicates that modem or data set is ready to establish a communications
link with UART.
Bit 5 in modem status register reflects this input.
Data Carrier Detect.
Indicates that modem or data set has detected data carrier signal.
Bit 7 in modem status register reflects this input.
I
Data Terminal Ready.
Indicates that UART is ready to establish a communications link with
modem or data set.
O
Bit 0 in modem control register controls this output.
Request To Send.
Indicates that UART is ready to transfer data to modem or data set.
Bit 1 in modem control register controls this output.
RTS
RI
O
I
Secondary
Secondary
Negative
Negative
Ring Indicator.
Indicates that modem or data set has received telephone ring indicator.
Bit 6 in modem status register reflects this input.
12/22
OKI [ OKI ELECTRONIC COMPONETS ]
