Technical Description
OMG-USB-485-1
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Technical Description
The
OMG-USB-485-1:
utilizes a USB UART. This chip features programmable
baud rate, data format, 128 byte Dual Port TX Buffer, and 384 byte Dual Port RX
Buffer. The RS-530/422/485 transceiver supports data rates up to 921.6K baud..
Features
•
Hot-Pluggable device that doesn’t require opening the case
•
No system resources are required (i.e. I/O ports or IRQ’s)
•
LED status indicators for “USB Enabled”, “TD”, and “RD”
Connector Pin Assignments (DB25 Male)
The
OMG-USB-485-1
complies with the EIA-530 pin out with the following
signals supported
Signal
Name
Pin #
Mode
GND
Ground
7
RDB
RX+
Receive Positive
16
Input
RDA
RX-
Receive Negative
3
Input
CTSB
CTS+
Clear To Send Positive
13
Input
CTSA
CTS-
Clear To Send Negative
5
Input
DSRB
DSR+
Data Set Ready Positive
22
Input
DSRA
DSR-
Data Set Ready Negative
6
Input
DCDB
DCD+
Data Carrier Detect Positive
10
Input
DCDA
DCD-
Data Carrier Detect Negative
8
Input
TDB
TX+
Transmit Positive
14
Output
TDA
TX-
Transmit Negative
2
Output
RTSB
RTS+
Request To Send Positive
19
Output
RTSA
RTS-
Request To Send Negative
4
Output
DTRB
DTR+
Data Terminal. Ready Positive
23
Output
DTRA
DTR-
Data Terminal Ready Negative
20
Output
