Integration Guide
Table Of Contents
- Preface
- Contents
- 1 System description
- 1.1 Overview
- 1.2 Architecture
- 1.3 Pin-out
- 1.4 Operating modes
- 1.5 Power management
- 1.6 System functions
- 1.7 RF connection
- 1.8 SIM interface
- 1.9 Serial Communication
- 1.10 Audio
- 1.11 ADC input (LEON-G100 only)
- 1.12 General Purpose Input/Output (GPIO)
- 1.13 M2M Setup Schematic Example
- 1.14 Approvals
- 2 Design-In
- 3 Handling and soldering
- 4 Product Testing
- Appendix
- A Extra Features
- B Glossary
- Related documents
- Revision history
- Contact
LEON-G100/G200 - System Integration Manual
GSM.G1-HW-09002-F3 Preliminary System description
Page 47 of 101
AT+UPSV
HW flow control
RTS line
Communication during idle mode and wake up
2
Disabled (AT&K0)
OFF
When a low-to-high transition occurs on the TxD input line, the module switches from
idle-mode to active-mode after 20 ms: this is the “wake up time” of the module. As a
consequence, the first character sent when the module is in idle-mode (i.e. the wake up
character) won’t be a valid communication character because it can’t be recognized, and
the recognition of the subsequent characters is guaranteed only after the complete wake-up
(i.e. after 20 ms).
Table 17: UART and power-saving summary
AT+UPSV=0: power saving disabled, fixed active-mode
The module doesn’t enter idle-mode and the CTS line is always held in the ON state after UART initialization. The
UART interface is enabled and data can be received. This is the default configuration.
AT+UPSV=1: power saving enabled, cyclic idle/active mode
The module automatically enters idle-mode whenever possible, and periodically wakes up from idle-mode to
active-mode to monitor the paging channel of the current base station (paging block reception), in accordance
to GSM system requirements.
Idle-mode time is fixed by network parameters and can be up to ~2.1 s. When the module is in idle-mode, a
data transmitted by the DTE will be lost if hardware flow control is disabled, otherwise if hardware flow control
is enabled, data will be buffered by the DTE and will be correctly received by the module when active-mode is
entered.
When the module wakes up to active-mode, the UART interface is enabled and data can be received. When a
character is received, it forces the module to stay in the active-mode for a longer time.
The active-mode duration depends by:
Network parameters, related to the time interval for the paging block reception (minimum of ~11 ms)
Time period from the last data received at the serial port during the active-mode: the module doesn’t enter
idle-mode until a timeout expires. This timeout is configurable by the +UPSV AT command, from 40 GSM
frames (~184 ms) up to 65000 GSM frames (300 s). Default value is 2000 GSM frames (~9.2 s).
Every subsequent character received during the active-mode, resets and restarts the timer; hence the active-
mode duration can be extended indefinitely.
The behavior of hardware flow-control output (CTS line) during normal module operations with power-saving
and HW flow control enabled (cyclic idle-mode and active-mode) is illustrated in Figure 28.
Figure 28: CTS behavior with power saving enabled: the CTS line indicates when the module is able (CTS = ON = low level) or
not able (CTS = OFF = high level) to accept data from the DTE and communicate through the UART interface
time [s]
CTS ON
CTS OFF
max ~2.1 s
UART disabled
min ~11 ms
UART enabled
~9.2 s (default)
UART enabled
Data input
time [s]
CTS ON
CTS OFF
max ~2.1 s
UART disabled
min ~11 ms
UART enabled
~9.2 s (default)
UART enabled