User's Manual

Table Of Contents
RB4000HM Switch settings:
This Switch is reserved for future use. Do not change. They all should be set to the OFF
position.
DTE Speed 1 2 3
115200
(Default)
OFF OFF OFF
RB4000HM Interface Signal Level Definitions
Pin # Pin Name Type Description I/O Voltage Range
1 KEY -
2 Not Used - No connection
3 LINK LED O Link LED output Vol: 0V ~ 0.2V
Voh: 2.8V ~ 3.3V
4 3.3 VDD PWR Supply voltage 3.15V ~ 3.45V
5 _RESET I Reset if low for more
than 5ms
Vil: 0V ~ 0.99V
Vih: 2.31V ~ 3.3V
6 GND - Ground
7 Reserved -
8 Reserved -
9 Reserved -
10 Reserved -
11 Reserved -
12 Reserved -
13 Reserved -
14 _CTS I UART clear to send
active low
Vil: 0V ~ 0.99V
Vih: 2.31V ~ 3.3V
15 Reserved -
16 Reserved -
17 _RTS O UART request to send
active low
Vol: 0V ~ 0.2V
Voh: 2.8V ~ 3.3V
18 _TX O UART data output Vol: 0V ~ 0.2V
Voh: 2.8V ~ 3.3V
19 _RX I UART data input Vil: 0V ~ 0.99V
Vih: 2.31V ~ 3.3V
20 Reserved -
15
Note: I/O is DTE not DCE. RTS and CTS functionality is for Hardware Flow
Control.