MeiG_SLM156_Hardware Design Manual
MeiG Smart Technology Co., Ltd
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SLM156 provides 1.8V serial port. If your application serial port is 3.3V, you need to add level converter.
It is recommended that you use TXB0104PWR from TI Company. Reference design is shown as
follows:
Figure 10 Reference Circuit of Level Conversion Chip
3.12 Network Status Indication
The network indication pins can be used to drive a network status indicator LED. SLM156 provides two
pins: The following tables describe pin STATUS and NET_STATUS .The following two tables show the
definition and logic level changes in different network status.
Table 13 Pin description of network indication
Pin name
Pin number
I/O
Description
Note
NETLIGHT
16
DO
Indicate the network status of
the module
1.8V power
domain
Table 14 Activity status of NET_STATUS
Mode
State
Description
NETLIGHT
Flicker slowly (200ms OFF/1800ms
ON)
Network search
Flicker quickly(1800ms OFF/200ms
ON)
Idle
