GSM/GPRS/NB-IoT Module Series
BC68&M66 Compatible Design
BC68&M66_Compatible_Design 12 / 31
5
RESERVED
/
/
SPK1P
AO
Channel 1
Positive voice output
6
RESERVED
/
/
SPK1N
AO
Channel 1
Negative voice output
7
RESERVED
/
/
PWRKEY
DI
Used to power on/off the
module
8
RESERVED
/
/
AVDD
PO
Reference voltage of
ADC circuit
9
ADC*
AI
General purpose
analog to digital
converter
ADC0
AI
General purpose analog
to digital converter
10
SIM_GND
USIM ground
SIM_GND
Specified ground for
USIM card
11
SIM_DATA
IO
USIM data
SIM_DATA
IO
(U)SIM card data signal
12
SIM_RST
DO USIM reset
SIM_RST
DO
(U)SIM card reset signal
13
SIM_CLK
DO USIM clock
SIM_CLK
DO
(U)SIM card clock signal
14
SIM_VDD
PO
Power supply for
USIM card
SIM_VDD
PO
Power supply for (U)SIM
card
15
RESET
DI
Reset the module
RESERVED
/
/
16
NETLIGHT*
DO
Network status
indication
NETLIGHT
DO
Network status indication
17
TXD
DO Transmit data
TXD
DO
Transmit data
18
RXD
DI
Receive data
RXD
DI
Receive data
19
DTR
DI
Data terminal
ready
DTR
DI
Data terminal ready
20
RI
DO Ring indication
RI
DO
Ring indication
21
RESERVED
/
/
DCD
DO
Data carrier detection
22
RESERVED
/
/
CTS
DO
Clear to send
23
RESERVED
/
/
RTS
DI
Request to send
24
VDD_EXT
PO
3.0V output power
supply for external
circuits.
It cannot be used
to supply power for
external circuits
when in PSM.
VDD_EXT
PO
Supply 2.8V voltage for an
external circuit.
