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. Power saving
- 3.6. Summary of state transitions
- 3.7. RTC backup
- 3.8. Serial interfaces
- 3.9. Audio interfaces
- 3.10. SIM card interface
- 3.12. Behaviors of the RI
- 3.13. Network status indication
- 3.14. 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
M95 Hardware Design
M95_HD_V1.0 - 55 -
VPP
C6
Not Connect
SIM_DATA
C7
SIM Card data I/O
3.12. Behaviors of the RI
Table 17: Behaviors of the RI
State
RI respond
Standby
HIGH
Voice calling
Change to LOW, then:
(1) Change to HIGH when call is established.
(2) Use ATH to hang up the call, change to HIGH.
(3) Calling part hangs up, change to HIGH first, and change to LOW for
120ms indicating “NO CARRIER” as an URC, then change to HIGH
again.
(4) Change to HIGH when SMS is received.
Data calling
Change to LOW, then：
(1) Change to HIGH when data connection is established.
(2) Use ATH to hang up the data calling, change to HIGH.
(3) Calling part hangs up, change to HIGH first, and change to LOW for
120ms indicating “NO CARRIER” as an URC, then change to HIGH
again.
(4) Change to HIGH when SMS is received.
SMS
When a new SMS comes, the RI changes to LOW and holds low level for
about 120 ms, then changes to HIGH.
URC
Certain URCs can trigger 120ms low level on RI. For more details, please
refer to the document [10].
If the module is used as a caller, the RI would maintain high except the URC or SMS is received.
On the other hand, when it is used as a receiver, the timing of the RI is shown below.
RI
Idle Ring
Off-hook by
“ATA”. On-hook
by “ATH”. SMS
received.
HIGH
LOW
Figure 32: RI behavior of voice calling as a receiver