Vehicle Intergrated Mobile Phone
I had been trying to come up with a way to integrate a Mobile Phone into my CAR-PC.
Some of the problems with intergrating a standard mobile phone:
A: Hard to find which Phones take AT commands via USB or Serial link and if so, do they implement the full command set?
B: Having to modify the phone to fit an aerial socket if no external connection is provided and having to modify Power control and audio as the Phone would never be touched again, it should act like another enbedded module in the CAR-PC system with everything displayed on the Vehicle 8" Touch screen, and it must be Touch screen and feDrive panel controlled.
Why do I want this?
The Car PC fully integrated into the vehicle, I want full intergration of the Phone software and I want things like:
1: Voice alerts and information on incoming calls and phone status like Missed SMS, Phone calls and coverage errors .
2: Auto switching to the Phone Menu on an incoming call with Phone number displayed on my 8" screen.
3: Caller name instead of Number displayed and Announced if they are in the Phone Book.
4: Option for Spoken Name of the Incoming caller if they are in the Phone Book.
5: Option to auto answer only calls in the Phone Book which resides on the Car PC.
6: Auto muting of the Radio, GPS and Music Player along with Pausing of the Music player etc when an incoming call is detected.
7: Auto return to Previous CAR-PC Menu state on disconnect and full resume of all Audio sources, un-paused players etc.
8: Answer or Make calls manually using Steering Wheel controls and Centre console feDrive control panel.
9: Signal strength indication.
10: Last 10 Phone calls received and last 10 SMS Message numbers received.
11: Big screen viewing of SMS messages with Simple control for sending them.
12: Being able to have the Vehicle send SMS alerts if the alarm is tripped.
13. Send GPS data to an FTP server as it’s moving, both Independent of the CAR-PC running.
14: Has to cost under $90.
Some of the problems with intergrating a standard mobile phone:
A: Hard to find which Phones take AT commands via USB or Serial link and if so, do they implement the full command set?
B: Having to modify the phone to fit an aerial socket if no external connection is provided and having to modify Power control and audio as the Phone would never be touched again, it should act like another enbedded module in the CAR-PC system with everything displayed on the Vehicle 8" Touch screen, and it must be Touch screen and feDrive panel controlled.
Why do I want this?
The Car PC fully integrated into the vehicle, I want full intergration of the Phone software and I want things like:
1: Voice alerts and information on incoming calls and phone status like Missed SMS, Phone calls and coverage errors .
2: Auto switching to the Phone Menu on an incoming call with Phone number displayed on my 8" screen.
3: Caller name instead of Number displayed and Announced if they are in the Phone Book.
4: Option for Spoken Name of the Incoming caller if they are in the Phone Book.
5: Option to auto answer only calls in the Phone Book which resides on the Car PC.
6: Auto muting of the Radio, GPS and Music Player along with Pausing of the Music player etc when an incoming call is detected.
7: Auto return to Previous CAR-PC Menu state on disconnect and full resume of all Audio sources, un-paused players etc.
8: Answer or Make calls manually using Steering Wheel controls and Centre console feDrive control panel.
9: Signal strength indication.
10: Last 10 Phone calls received and last 10 SMS Message numbers received.
11: Big screen viewing of SMS messages with Simple control for sending them.
12: Being able to have the Vehicle send SMS alerts if the alarm is tripped.
13. Send GPS data to an FTP server as it’s moving, both Independent of the CAR-PC running.
14: Has to cost under $90.
I found this module that has Microphone IN and Line OUT connections, 12v power connector and USB or serial connections and cost was only $45.00.
It supports Voice, SMS, Data/Fax, GPRS and has an integrated TCP/IP stack.
It supports Voice, SMS, Data/Fax, GPRS and has an integrated TCP/IP stack.
Features:
Single-IC: AMR926EJ-S core
SMT
Quad-Band 2G
GPRS Class 10/8
Embedded TCP/IP
Quad-Band 850/ 900/ 1800/ 1900 MHz
GPRS multi-slot class 10/8
GPRS mobile station class B
Compliant to GSM phase 2/2+
Class 4 (2 W @850/ 900 MHz)
Class 1 (1 W @ 1800/1900MHz)
Control via AT commands:
(GSM 07.07, 07.05 and SIMCOM enhanced AT Commands)
Low power consumption: 1.5mA (sleep mode)
Operation temperature: -40 °C to +85 °
Single-IC: AMR926EJ-S core
SMT
Quad-Band 2G
GPRS Class 10/8
Embedded TCP/IP
Quad-Band 850/ 900/ 1800/ 1900 MHz
GPRS multi-slot class 10/8
GPRS mobile station class B
Compliant to GSM phase 2/2+
Class 4 (2 W @850/ 900 MHz)
Class 1 (1 W @ 1800/1900MHz)
Control via AT commands:
(GSM 07.07, 07.05 and SIMCOM enhanced AT Commands)
Low power consumption: 1.5mA (sleep mode)
Operation temperature: -40 °C to +85 °
It's basically a Hardware only version of a mobile phone. It does FTP, DATA (HTML), Voice, SMS etc. So pretty much anything you want it to do.
This unit is 2.5G so data rate is not 3G but it’s perfect for sending GPS location to an FTP server etc and, of course SMS messages and Voice calls.
Plug in a standard SIM and plug the module into a USB port on the Computer and it's ready to go, except of the Phone application that is needed to control it.
Armed with the AT command set documentation, I spent a week or so writing the software and now have it all working.
FYI. The AT command set goes back to the early days of Modems and is still used in Mobile Phones to control them externally. There is no standardization across ALL commands or the data that the command operates with or returns.
This unit is 2.5G so data rate is not 3G but it’s perfect for sending GPS location to an FTP server etc and, of course SMS messages and Voice calls.
Plug in a standard SIM and plug the module into a USB port on the Computer and it's ready to go, except of the Phone application that is needed to control it.
Armed with the AT command set documentation, I spent a week or so writing the software and now have it all working.
FYI. The AT command set goes back to the early days of Modems and is still used in Mobile Phones to control them externally. There is no standardization across ALL commands or the data that the command operates with or returns.
Size in comparison to a small mobile Phone
End view showing SIM socket and Aerail connection
BTW: For anyone interested, I’m also writing this Phone software as a standalone application that’s not tied into my Front End software, as well as a version fully integrated into the FE.
There are new 3G units out there but most are still expensive, a few hundred dollars last time I looked. The small Aluminium case unit above was $45.00. With any of these you normally need to write you own software.
There are new 3G units out there but most are still expensive, a few hundred dollars last time I looked. The small Aluminium case unit above was $45.00. With any of these you normally need to write you own software.
Audio quality both ways is beautiful, however the problem of ECHO is there and is to be expected considering the Caller audio is fed through the vehicle Sound system and therefore acoustically coupled back into the MIC.
There are adjustable Echo controls built into the Phone Module however it was never intended for use in such an amplified and separated environment. The cure was a Phoenix Audio MT107A ECHO cancelling DSP unit.
The MIC and Speaker level (Line out) settings in the Phone are critical to getting this device to work correctly. I’ve seen posts where people get echo cancellation to work well with some phones and not others, I wonder if this is the difference. With this Phone module I have complete control over both gain settings.
There are two paths for echo in the phone, the internal duplex circuit and the amplified external Hands free circuit.
I have drawn a quick connection layout for anyone interested. At this stage I was initally using a resistor to reduce the speaker level down to line level for the system audio out sound sample. I later found an easy analogue tap off point on the amp, I’m using an Optical output connection from the PC to the AMP via a DSP graphic equalizer.
I found I had Left and Right Pre outputs that sum the two left channels and two right channels before the level-control (non fading outputs) on the Alpine AMP. These summed Pre Outs now feed the MT107A speaker sample inputs instead of using my (temp get it going in a hurry) isolation transformer and resistive divider that was initally connected to one of the speakers.
The echo has been virtually eliminated on calls to other mobiles and it was particularly bad on the other mobile when it was also running hands-Free. No problems at all now. When testing this final connection with a few calls to mobile and landline phones running hands-free, if I unplug the speaker sample lead, the other phones hear so much return echo that it’s almost impossible for them to have a conversation with me, plug the sample lead back into the MT107A and there is absolutely ZERO echo even with the volume level in the car wound “way way up”, the MT107A is a brilliant device.
Note: The MT107A is also used for Voice activated control in many vehicle systems.
There are adjustable Echo controls built into the Phone Module however it was never intended for use in such an amplified and separated environment. The cure was a Phoenix Audio MT107A ECHO cancelling DSP unit.
The MIC and Speaker level (Line out) settings in the Phone are critical to getting this device to work correctly. I’ve seen posts where people get echo cancellation to work well with some phones and not others, I wonder if this is the difference. With this Phone module I have complete control over both gain settings.
There are two paths for echo in the phone, the internal duplex circuit and the amplified external Hands free circuit.
I have drawn a quick connection layout for anyone interested. At this stage I was initally using a resistor to reduce the speaker level down to line level for the system audio out sound sample. I later found an easy analogue tap off point on the amp, I’m using an Optical output connection from the PC to the AMP via a DSP graphic equalizer.
I found I had Left and Right Pre outputs that sum the two left channels and two right channels before the level-control (non fading outputs) on the Alpine AMP. These summed Pre Outs now feed the MT107A speaker sample inputs instead of using my (temp get it going in a hurry) isolation transformer and resistive divider that was initally connected to one of the speakers.
The echo has been virtually eliminated on calls to other mobiles and it was particularly bad on the other mobile when it was also running hands-Free. No problems at all now. When testing this final connection with a few calls to mobile and landline phones running hands-free, if I unplug the speaker sample lead, the other phones hear so much return echo that it’s almost impossible for them to have a conversation with me, plug the sample lead back into the MT107A and there is absolutely ZERO echo even with the volume level in the car wound “way way up”, the MT107A is a brilliant device.
Note: The MT107A is also used for Voice activated control in many vehicle systems.
The basic connections are pretty simple.
1. Microphone In.
2. Audio Line out.
3. 12V to 18V In.
4. GPS aerial.
1. Microphone In.
2. Audio Line out.
3. 12V to 18V In.
4. GPS aerial.
Phoenix MT107A supplied software for fine tuning the Microphone audio, filtering and levels.
This system automatically mutes all other sound and pops up automatically on an incoming call. It will auto answer anyone in the phone book and announce their name.
A touch of the encoder button mounted between the seats will manually answer any other call and hangup when finished.
It is designed correctly for touch screen display and like all information in the Front End, audio prompts are available.
For most calls this is a totally Auto Answer - Auto Hangup system with beautiful hands free audio through the vehicle sound system.
A touch of the encoder button mounted between the seats will manually answer any other call and hangup when finished.
It is designed correctly for touch screen display and like all information in the Front End, audio prompts are available.
For most calls this is a totally Auto Answer - Auto Hangup system with beautiful hands free audio through the vehicle sound system.
Setup Menu: Basically all settings needed for the module to work with my software are here. If a new module were to be connected, just run through each item and press the write button.
Current setting along with updated settings are decoded and displayed in english.
The function of each command is shown in the lower window and the current AT command is shown on the Button. Pressing the test button loads the current command into an edit line so the command can be sent and read back in native format. This allows them to be compared to actual command results in the AT programming document/manual for testing.
Of course any AT command can be entered and tested here.
Current setting along with updated settings are decoded and displayed in english.
The function of each command is shown in the lower window and the current AT command is shown on the Button. Pressing the test button loads the current command into an edit line so the command can be sent and read back in native format. This allows them to be compared to actual command results in the AT programming document/manual for testing.
Of course any AT command can be entered and tested here.
Car-PC Phone Software:
Phone Answer options:
1: Auto answer only for entries in the Phone book.
2: Optional Voice announcement of the Phone Book caller Name onconnect.
3: Auto answers all call.
4: Both enabled with X number of rings before answering a Non Phonebook call.
5: Manual answer and Hang up with a touch of the feDrive encoder.
6: Auto Mute and Pause of Media on phone ring or when dialling a number.
7: Auto switching to the Phone app on an incoming call.
8: Auto resume and un-mute of media at disconnect with return to previous FE menu.
SIM PIN options:
1: PIN code required enable/disable.
2: Auto entry of the PIN code at power up (with vehicle security detect before Phone unlock)
3: Manual entry of PIN code with Retry count displayed.
4: New PIN entry code or change of PIN code.
5: PUK needed Display (over 3 incorrect PIN inputs) with PUK un-lock tested.
6: Auto Save and update (encrypted) for auto PIN with changed passwords.
Error Detection
1: No communications.
2: Phone Off
3: SIM missing.
4: SIM registration state.
5: Phone state.
6: Every other error state that I could find, induce or think of.
Information Displayed:
1: Full Phone call status from Phone ringing to Phone disconnect.
2: Caller ID if available, with Phone book entry indication.
3: Audible reminder if Phone has a connection for any unknown reason.
4: Missed Calls, last 10 with Phone numbers.
5: Missed SMS, last 10.
6: Display all SMS, delete ETC.
7: Phone Number Retrieval from SMS messages with reply or ring phone number option.
8: OSK for writing SMS.
9: Everything that the Phone is doing when not idle.
Phone Answer options:
1: Auto answer only for entries in the Phone book.
2: Optional Voice announcement of the Phone Book caller Name onconnect.
3: Auto answers all call.
4: Both enabled with X number of rings before answering a Non Phonebook call.
5: Manual answer and Hang up with a touch of the feDrive encoder.
6: Auto Mute and Pause of Media on phone ring or when dialling a number.
7: Auto switching to the Phone app on an incoming call.
8: Auto resume and un-mute of media at disconnect with return to previous FE menu.
SIM PIN options:
1: PIN code required enable/disable.
2: Auto entry of the PIN code at power up (with vehicle security detect before Phone unlock)
3: Manual entry of PIN code with Retry count displayed.
4: New PIN entry code or change of PIN code.
5: PUK needed Display (over 3 incorrect PIN inputs) with PUK un-lock tested.
6: Auto Save and update (encrypted) for auto PIN with changed passwords.
Error Detection
1: No communications.
2: Phone Off
3: SIM missing.
4: SIM registration state.
5: Phone state.
6: Every other error state that I could find, induce or think of.
Information Displayed:
1: Full Phone call status from Phone ringing to Phone disconnect.
2: Caller ID if available, with Phone book entry indication.
3: Audible reminder if Phone has a connection for any unknown reason.
4: Missed Calls, last 10 with Phone numbers.
5: Missed SMS, last 10.
6: Display all SMS, delete ETC.
7: Phone Number Retrieval from SMS messages with reply or ring phone number option.
8: OSK for writing SMS.
9: Everything that the Phone is doing when not idle.