15 external i 2c serial control bus, 16 tx_on - burst transmission, 15 external i – Sony Ericsson GM47 User Manual
Page 65: C serial control bus, The i
2. SYSTEM CONNECTOR INTERFACE
65
LZT 123 7263 R1C
2.15 External I
2
C Serial Control Bus
Note!
The I
2
C bus is currently not supported by the software
The external I
2
C bus consists of two signals, SDA and SCL. This bus
is isolated from the module’s internal I
2
C bus to ensure proper
operation of the module, even if the external I
2
C bus is damaged.
The electrical characteristics are shown below.
2.16 TX_ON - Burst Transmission
Burst transmission is the time when a GSM transceiver unit is
transmitting RF signals. TX_ON indicates the module is going into
transmission mode.
Pin
Signal
Dir
Description
29
SDA
I/O
I
2
C serial data
30
SCL
O
I
2
C serial clock
Parameter
Min.
Typ.
Max.
Units
Tr
a
n
sm
it
oper
ation
Frequency I
2
C CLK
81.25
400
kHz
High or low I
2
C CLK
1.2
µs
Delay time after falling edge of I
2
C
CLK
308
308-
1230
ns
Hold time after falling edge of I
2
C
CLK
0
ns
Rec
e
iv
e
oper
at
ion
Frequency I
2
C CLK
400
kHz
High or low I
2
C CLK
1.2
µs
Delay time after falling edge of I
2
C
CLK
100
ns
Hold time after falling edge of I
2
C
CLK
0
ns
Pin
Signal
Dir
Description
35
TX_ON
O
GSM module to transmit