User's Manual
Table Of Contents
- Contents
- Table Index
- Figure Index
- 0. Revision history
- 1. Introduction
- 2. Product concept
- 3. Application interface
- 3.1. Pin
- 3.2. Operating modes
- 3.3. Power supply
- 3.4. Power on and down scenarios
- 3.5. Charging interface
- 3.6. Power saving
- 3.7. Summary of state transitions
- 3.8. RTC backup
- 3.9. Serial interfaces
- 3.10. Audio interfaces
- 3.11. SIM card interface
- 3.12. SD card interface
- 3.13. PCM interface
- 3.14. ADC
- 3.15. Behaviors of the RI
- 3.16. Network status indication
- 3.17. Operating status indication
- 4. Antenna interface
- 5. Electrical, reliability and radio characteristics
- 6. Mechanical dimensions
- 7. Storage and manufacturing
- Appendix A: GPRS coding schemes
- Appendix B: GPRS multi-slot classes
M80 Hardware Design
M80_HD_V1.2 - 43 -
Figure 17: Seiko XH414H-IV01E Charge Characteristics
3.9. Serial interfaces
The module provides three serial ports: UART Port, Debug Port and Auxiliary UART Port. The
module is designed as a DCE (Data Communication Equipment), following the traditional
DCE-DTE (Data Terminal Equipment) connection. Autobauding function supports baud rate from
4800bps to 115200bps.
The UART Port:
TXD: Send data to RXD of DTE.
RXD: Receive data from TXD of DTE.
RTS: Requests to send.
CTS: Clear to send.
DTR: DTE is ready and inform DCE (this pin can wake the module up).
RI: Ring indicator (when the call, SMS, data of the module are coming, the module will
output signal to inform DTE).
DCD: Data carrier detection (the validity of this pin demonstrates the communication link is
set up).
Note: The module disables hardware flow control by default. When hardware flow control is
required, RTS and CTS should be connected to the host. AT command “AT+IFC=2,2” is used to
enable hardware flow control. AT command “AT+IFC=0,0” is used to disable the hardware
flow control. For more details, please refer to document [1].