4. Jumper Setting
SPI-8550-LLVAS
37
Setting the RS-422/RS-485 receiver disable control jumper
When the RS-422/RS-485 port is used, the RTS signal is used for driver enable control Connecting JP8
Pins 4 and 6 set to OFF disables the receiver at the same time, preventing the port from receiving output
data to an external device.
RS-422 Setting
RTS#
JP8: 7-8
TXD#
TX-
RTS-
TX+
RTS+
RX+
CTS+
RX-
CTS-
JP7: 7-8
JP7: 5-6
JP7: 3-4
JP7: 1-2
D
R
D
R
RXD#
RTS
CTS
COM2
1
2
3
4
5
6
7
8
9
JP8: 5-6
JP8: 4-6
120
Ω
120
Ω
120
Ω
120
Ω
Figure 4.1. RS-422 Setting
RS-485 Setting
RTS#
JP8: 7-8
TXD#
JP7:7-8
JP7:5-6
D
R
RXD#
COM2
1
2
3
4
5
6
7
8
9
JP8: 5-6
JP8: 4-6
120 Ω
120 Ω
DATA-
DATA+
Figure 4.2. RS-485 Setting
Summary of Contents for SPI-8550-LLVAS
Page 7: ...vi SPI 8550 LLVAS...
Page 13: ...1 Introduction 6 SPI 8550 LLVAS...
Page 19: ...2 System Reference 12 SPI 8550 LLVAS...
Page 47: ...4 Jumper Setting 40 SPI 8550 LLVAS...
