Use Instructions
Table Of Contents
- 1 About this document
- 2 Product Overview
- 3 Interface Description
- 3.1 PIN Definition
- 3.2 Operating condition
- 3.3 Digital I/O characteristics
- 3.4 Power Interface
- 3.5 UIM interface
- 3.6 PCM interface(TBD)
- 3.7 USB2.0 interface
- 3.8 UART Interface
- 3.9 Power on/off and reset interface
- 3.10 Interactive interface
- 3.11 Net Light interface
- 3.12 System boot configuration and download
- 3.13 Analog and Digital conversion (ADC) interface
- 3.14 I2C interface
- 3.15 SPI interface
- 3.16 Antenna interface
- 4 Product characteristics
- 5 Design guideline
- 6 Manufacturers
- 7 Package Storage information
- 8 Safety Information
L710HG Hardware Design
30
3.9 Power on/off and reset interface
3.9.1 Pin definition
The power-on sequence of this product is:
Pull down the PWRKEY pin and input a low pulse of about 1s to the boot signal. Then
suspend or pull up the pin to start the machine.
The PWRKEY pin has its own reset function. The hardware reset requires the PWRKEY
pin to be pulled down for 12 seconds, and the module system can only reset and power-on
after 12s.
The PWRKEY is not allowed to connect directly to the ground, and can only be turned on
with a short key touch or input pulse waveform.
Table 3-13 power on/off and reset key define
Pin No.
Net name
I/O
Typ. descriptions
36 PWRKEY DI L710HG power on/off /reset pin (
internal
pull-up to 1.5V)
3.9.2 Power on sequence
Table 3-14 power on timing chart.
SYMBOL
SIGNAL
MIN.
TYP. MAX. UNIT
Ton
Power on low level pulse 1 -- -- s
Ton(status) Power
on time (According to the
STATUS pin judgment)
2.5 -- -- s
Ton(uart) Power on time (according the UART
pin judgement)
2.5 -- -- s
VIH
Input high level voltage of
PWRKEY pin
1.17 1.5 1.8 V
VIL Input low level voltage of PWRKEY
pin
-0.3 0 0.3 V
Figures 3-15 Power on Timing sequence
Note: 1. Ton is the PWRKEY hardware de-bounce time. User must keep this time for system start