9 serial com1 – com2 ports (j19, j18), Serial com1 – com2 ports (j19, j18) – Kontron KTQM87-mITX User Manual
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KTD-N0886-A
Page 36
Internal Connectors
KTQM87/mITX Users Guide
Serial COM1 – COM2 Ports (J19, J18)
7.9
Two RS232 serial ports are available on the KTQM87.
The typical definition of the signals in the COM ports is as follows:
Signal Description
TxD
Transmitted Data, sends data to the communications link. The signal is set to the marking state (-
12V) on hardware reset when the transmitter is empty or when loop mode operation is initiated.
RxD
Received Data, receives data from the communications link.
DTR
Data Terminal Ready, indicates to the modem etc. that the on-board UART is ready to establish a
communication link.
DSR
Data Set Ready, indicates that the modem etc. is ready to establish a communications link.
RTS
Request To Send, indicates to the modem etc. that the on-board UART is ready to exchange data.
CTS
Clear To Send, indicates that the modem or data set is ready to exchange data.
DCD
Data Carrier Detect, indicates that the modem or data set has detected the data carrier.
RI
Ring Indicator, indicates that the modem has received a ringing signal from the telephone line.
The pinout of Serial ports COM1 (J19), COM2 (J18)
Note Ioh/Iol Type Signal PIN
Signal Type Ioh/Iol Note
-
I
DCD
1 2
DSR
I
-
-
I
RxD
3 4
RTS
O
O
TxD
5 6
CTS
I
-
O
DTR
7 8
RI
I
-
-
PWR GND
9 10
5V
PWR -
1
Note 1: The COM1, COM2 5V supply is fused with common 1.5A resettable fuse.
DB9 adapter cables (PN 821016 200mm long and 821017 100mm long) are available for implementing
standard COM ports on chassis.
Available cable kit (DB9 adapter cables):
PN 821017 - 100 mm or PN 821016 - 200 mm