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OG_MU-D1-R_v10e Circuit Design, Inc.
8
OPERATION GUIDE
The MU-D1-R transmits user data in serial data format using
the UART input/output port (TXD terminal and RXD terminal).
Level conversion is required for connection to RS232. The
RS232C DSR signal must be supported by the user's circuit
board.
The function of each terminal is shown in the table below.
Unused terminals should be set to open.
The control CPU used with this equipment is the NEC
µ
PD78F0537GA with a CMOS structure. The thresholds for
Low level and High level are V
DD
× 0.2 and V
DD
× 0.8
respectively, based on the supply voltage V
DD
.
Terminal
No.
Terminal
name
I/
O
Description
Internal circuit
1
TXD
O The serial data transmit terminal.
470Ω
47kΩ
Vcc
CPU Port
Terminal
2
RXD
I
The serial data receive terminal.
470Ω
47kΩ
Vcc
CPU Port
Terminal
3
RTS
O
The hardware flow control signal output terminal.
If the internal status is not busy, the status is Low
and data can be received via the RXD terminal. If
the internal status is busy, the status is High and
data cannot be received.
470Ω
47kΩ
Vcc
CPU Port
Terminal
4
CTS
I
The hardware flow control signal input terminal.
Determines that the unit is not busy when the
status is Low, and sends data from the TXD
terminal.
Determines that the unit is busy when the status is
High, and does not send data.
470Ω
47kΩ
Vcc
CPU Port
Terminal
5
MOD
(MODE)
I
Switches between the command mode, binary
mode, or text mode.
In the command mode when set to High, and the
binary mode or text mode when set to Low.
470Ω
47kΩ
Vcc
CPU Port
Terminal
2.2 Terminal Specifications
MU-D1-R Terminal name, Terminal No. (Top view)