User's Manual

Table Of Contents
M80 Hardware Design
M80_HD_V1.2 - 26 -
LOUDSPKP
14
positive and
negative
voice-band output
keep these pins
open.
2. Embedded
amplifier of class
AB internally.
3. Support both
voice and ring.
Net status indicator
PIN NAME
PIN
NO.
I/O
DESCRIPTION
DC
CHARACTERISTICS
COMMENT
NETLIGHT
4
O
Network status
indication
VOHmin=
0.85×VDD_EXT
VOLmax=
0.15×VDD_EXT
If unused, keep
these pins open.
UART Port
PIN NAME
PIN
NO.
I/O
DESCRIPTION
DC
CHARACTERISTICS
COMMENT
DTR
47
I
Data terminal
ready
VILmin=0V
VILmax=
0.25×VDD_EXT
VIHmin=
0.75×VDD_EXT
VIHmax=
VDD_EXT+0.3
VOHmin=
0.85×VDD_EXT
VOLmax=
0.15×VDD_EXT
If only use TXD,
RXD and GND
to communicate,
recommend
keeping other
pins open except
RTS. Pull down
RTS.
RXD
50
I
Receive data
TXD
49
O
Transmit data
RTS
51
I
Request to send
CTS
48
O
Clear to send
RI
46
O
Ring indicator
DCD
45
O
Data carrier
detection
Debug Port
PIN NAME
PIN
NO.
I/O
DESCRIPTION
DC
CHARACTERISTICS
COMMENT
DBG_TXD
42
O
UART interface for
debugging only.
VILmin=0V
VILmax=
0.25×VDD_EXT
VIHmin=
0.75×VDD_EXT
VIHmax=
VDD_EXT+0.3
VOHmin=
0.85×VDD_EXT
VOLmax=
0.15×VDD_EXT
If unused, keep
these pins open.
DBG_RXD
43
I
Auxiliary UART Port