Stollmann BlueEva+C11/G2, Руководство пользователя

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Stollmann
E + V GmbH
C11/G2
User Guide
Author: ta Date saved: 06.04.09 Ref: C11G2_User_Guide_r02.doc Revision: r02 Page 21 of 22
6 RS-485 Interface
From firmware version 1.208 the C11/G2 can be configured for RS-485
operation. Additionally an RS-485 hardware interface is needed.
The schematic of this interface based on the MAX3491E transceiver is shown
below. It can be configured for 2 or 4 wire and full- or half duplex operation by
jumpers.
Jumper Number Position Description
J1
2-3 Half duplex mode (RTS connected to /RE)
J1 1-2 Full duplex mode (/RE connected to GND)
J2 Close for two wire mode (half duplex)
J3 Close for two wire mode (half duplex)
J4 close Transmitter enable
J5 Close for bus termination with 120R
J6 Close for bus termination with 120R
7 Restrictions
Not all firmware versions support DTE mode nor RS-485.
R1
R2
+
27
29
31 32
30
28
UART_Tx UART_RTS
UART_Rx
+3,3V GND
RxD
RTS
TxD
J4
J1
2
3
4
5
+
+3,3V
GND
VCC GND
R
D
RO
RE
DE
DI
12
11
A
B
Z
Y
10
9
14
6,7
J2
J3
J5
J6
GND
A
B
Z
Y
R1,R2 = 120R
MAX3491E
GND
1 2 3