V1.4
– Apr-13
User’s Manual
Page 22 of 34
5.2 Description A2035-H Signals
Table 5: Pin description A2035-H
Pin
Symbol
Function
Description
1
nRST
Input
Reset input, active low
2
BOOTSEL
Input
Special boot mode
– leave open for normal operation; 1.8V for
boot loader active
3
Vcc
Power Supply
3.0
– 3.6 V DC
4
WAKEUP
Output
-Status of digital section
(High = ON ,Low = OFF)
-Connect it to ON_OFF pin for self-start mode
5
Vout
Voltage Output
Permanent 1.8V voltage output for up to 20mA current max.
6
GND
Power Supply
Ground (power supply)
7
GPIO6 /
CTS/
SPI CLK
Input
Configuration pin for communication mode. 10K to 1.8V for
UART mode; leave open for SPI mode.
SPI clock pin when module works in SPI mode
8
GPIO7 /
RTS/
SPI CS
Input
SPI chip select pin when module works in SPI mode
9
GND
Power Supply
Ground (power supply)
10
NC
None
Mechanical fixture only
11
NC
None
Mechanical fixture only
12
NC
None
Leave open
13
NC
None
Leave open
14
ExtInt 2 /
GPIO4
Input
External interrupt input pin
– reserved for future use, leave open
15
TM_GPIO5
Output
Time Mark
– 1PPS signal
16
I2C CLK
Output
I2C clock Output to MEMS interface
17
I2C DIO
Input/Output
I2C I/O to MEMS interface
18
ON_OFF
Input
Connect to push-pull output is mandatory.
- Set to LOW by default
- Toggle to HIGH and back to LOW
> for first start-up after power on
> to request a fix in SiRFaware
TM
or PTF mode
> to go into or wake up out of hibernate mode
- Connect it to WAKEUP pin for self-start mode
19
ExtInt /
GPIO8
Input
Interrupt input for MEMS interface.
(If ExtInt is not going to be used, it is recommended that this pin
be tied directly to ground. Otherwise, a 100K pull-down resistor to
ground should be connected to the ExtInt pin.)
20
TX0 / SPI DO Output
Serial output 0.
NMEA out if configured for UART;
SPI data out pin when module works in SPI mode
21
RX0 / SPI DI
Input
Serial input 0.
NMEA in if configured for UART;
SPI data in pin when module works in SPI mode
