76 Threads found on edaboard.com: sim908
Actually, the GPS by SMS can not meet the market requirement now.
What about using SMS+Free GPRS platform.
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Microcontrollers :: 14.03.2012 22:15 :: wynnyeen :: Replies: 70 :: Views: 20205
I'm using sim908-C and have designed the hardware as described in its hardware design document. My issue is i'm not getting any voltage on SIM VDD and sim908-C is unable to find network i.e. relevant LED blink rate does not decrease.
When I power up the module I see some mV on SIM VDD for very short time then it reduces to 0V.
Analog Circuit Design :: 02.03.2012 02:00 :: engr.waqas :: Replies: 8 :: Views: 2618
Can anybody recommend a development board that has a sim908 GPRS+GPS and a ARM MCU on the same board? I had been looking but couldn't find anything.
Professional Hardware and Electronics Design :: 05.04.2012 16:21 :: scofmb :: Replies: 1 :: Views: 1078
i need sim908 schematic and footprint in altium designer. please reply a link if available...:-|
PCB Routing Schematic Layout software and Simulation :: 16.04.2012 07:58 :: behnam9856 :: Replies: 9 :: Views: 2452
I already have that schematic (Evaluation Board sch).
Could you share your schematic v57ali? Or could you send it to me, firstname.lastname@example.org?
Hi Rod_O ,
I just read your post and think that maybe this schematic may give you an opinion
Digital communication :: 24.11.2012 09:01 :: Rod_O :: Replies: 17 :: Views: 3766
A 78M05?????? Didn't you read the sim908 datasheet?
Digital communication :: 04.05.2012 17:10 :: Kosh :: Replies: 40 :: Views: 5149
After sim908 connecting to the server, I sent data with command AT+CIPSEND=.
When it respond the prompt "> ", I enter data.
Then wait for a long time, the modem respond "SEND OK".
The timeout is quite long (about 8-12s), so i want to improve this problem.
What command that I miss? or this is caused by server.
Microcontrollers :: 04.06.2012 03:34 :: ThiVu :: Replies: 0 :: Views: 734
I buy a sim908,but pins 59(GSM-ANT) with 60(GND) are short circuit,while pin 79(GPS-ANT) is not connected to (GND),Does anyone have this problem?
Digital communication :: 10.06.2012 14:23 :: arashghafary :: Replies: 1 :: Views: 512
I am using sim908 GPS_ANT pad to connection to an SMB connector from where it is connected to external(passive) GPS antenna. But sim908 is unable to track even a single satellite. I have used other GPS modules and signal loss due to impedance mismatch can cause degradation of signal resulting in less satellites being tracked. But in this case not a
PLD, SPLD, GAL, CPLD, FPGA Design :: 04.07.2012 04:12 :: McuGuy :: Replies: 2 :: Views: 850
Hi, I think the problem is the passive GPS antenna.
sim908 must be used with active GPS antenna (which includes a LNA - low noise amplifier).
I use a active patch antenna with build-in 28dB LNA.
Digital communication :: 11.10.2012 22:33 :: mgdaubo :: Replies: 1 :: Views: 1086
I am having a sim908 EVM board. I was able to send AT Commands and receive GPS data from a hyper terminal and a PIC24F.
My next step is to send the GPS data to a backend server over a HTTP POST. I inserted a sim card in the EVM Board. I am using a normal power supply provided in the EVM kit. The VBAT LED is steady Blue, the GSM_NET Le
Digital communication :: 16.07.2012 16:46 :: staples07 :: Replies: 4 :: Views: 1432
FYI -> most of GPS modules or rather what we manufacture (28dB LNA + 3dBi Ceramic CP antenna) require a minimum of 3.3 ~ 3.5V for operation. Please do cross check on this and also check the datasheet from your vendor.
I do not have thorough knowledge on sim908 module though.
Digital communication :: 10.08.2012 08:30 :: vedagarbhamsandeep :: Replies: 11 :: Views: 2951
where can i find the datasheet of simcom sim908 with its pin outs..
i found the sim908-c pinouts but i need sim908 only.
if any one has the information about sim908 please share it to me
Microcontrollers :: 24.07.2012 03:06 :: kvtal :: Replies: 4 :: Views: 919
I have a problem with sim908 module.
i can't transmit or receive from sim908. I use max3232 3.3V buffer to Rs232 to PC.
With same schematic I did it before. I can call, send message, add contact,GPS .... Now i can't commucation with sim908. Please help me i need it to finish my project. This is my schematic.77686
Microcontrollers :: 25.07.2012 02:52 :: quanghuydck :: Replies: 4 :: Views: 685
My projects uses the sim908 module ... works fine with only one issue.
The GPS stops responding after say 48 hurs of use, have to reset the system and it starts working again.
any idea the GSM part works fine receives and sends SMS even when the GPS is down.
any help is good
Digital communication :: 30.07.2012 05:31 :: rajuroshan :: Replies: 0 :: Views: 365
go through this link hope that it will help you....
best of luck
Microcontrollers :: 04.09.2012 05:07 :: prafful :: Replies: 3 :: Views: 1537
I'm working on gps project based on sim908 module. But my sim908 module is not responding. Network LED connected to it also not working. I don't have any circuitry to communicate serially with PC. But when i Checked the status pin the voltage on it is always less than 2.3 volt. The VDD-EXT pin is also less than 2.3 volt. I hadn't used any circ
Digital communication :: 27.09.2012 07:07 :: jithinrajnj :: Replies: 2 :: Views: 535
The sim908 GPS/GPRS module I'm developing with is having problems registering with my local towers.
I can plug in it and communicate with the UART just fine. It doesn't seem to be a power issue as the module doens't power off or report low voltage. There is a GSM antenna attached, and the signal appears to be good. The NET LED is flashing for a
Digital communication :: 01.10.2012 23:23 :: rbarber :: Replies: 1 :: Views: 745
the firmware of sim900 could not be used in sim908 the firmware of sim908 will fix this problem
Digital communication :: 09.10.2012 02:01 :: balucyber124 :: Replies: 2 :: Views: 860
I am planing to use Embedded AT comments of sim908 using sim908IDE software.
But looks like sim908IDE software needs RVCT2.2 (ARM) compiler.
Can anyone suggest where can i find this compiler and what would be the cost for the same.
Thanks in advance.
Digital communication :: 06.11.2012 05:19 :: jayamohan :: Replies: 0 :: Views: 487
I tried compiling a sample SMS project using sim908 IDE.
I just want to make sure the compilation is fine and no any error occurred.
I attached the screenshot of SIMIDE window.
Can some one verify the screen shots and let me know, the things are fine or any compiler issue is there.
Note: I yet to purchase the sim908 EVK.
Digital communication :: 08.11.2012 05:00 :: jayamohan :: Replies: 0 :: Views: 403
sim908 output altitude is in meters or dmeters ?
Because where I am, is 7 meters approximately over the sea, and the output of sim908 is "68.382" !
Thank you !
Microcontrollers :: 16.12.2012 09:32 :: anerDev :: Replies: 0 :: Views: 215
please somebody have electronic circuit for sim908, ???
Hobby Circuits and Small Projects Problems :: 17.12.2012 17:04 :: juliodv :: Replies: 0 :: Views: 540
I am doing a project on vehicle tracking system. Please do suggest me which one is best is it sim548c module or sim908. I am thinking of buying one of its evaluation board kit of very low cost one. can u please suggest me where to buy the best and cheapest one.
Digital communication :: 15.01.2013 20:32 :: rajath s :: Replies: 1 :: Views: 264
I know that sim908 has not LNA in the GPS section. What performance can be expected if I connect a passive ceramic patch antenna directly to the module?
Any comments or experiences will be appreciated.
Digital communication :: 29.01.2013 13:41 :: reinoso :: Replies: 0 :: Views: 250
I am new for sim908 ,i have stm32f103 microcontroller and USART1 of microcontroller is connected to sim908's microcontroller so i dont know how to interact with sim908 by stm32f103 i read AT COMMANDS but i cant interface with sim908 and unable to send AT COMMANDS please if anybody have the solution tell (...)
Microcontrollers :: 01.02.2013 06:56 :: mohanpatil :: Replies: 0 :: Views: 198
I know without sim908 we can not send AT COMMANDS but i want to interact by microcontroller of stm32f103ve and in my application board UART OF stm32f103ve is connected to UART of sim908 (pin15 and pin16) i tried to send the command by UART TX PIN OF stm32f103ve but the problem is the status of RESETING The flag of STM32F103ve is done b
Digital communication :: 01.02.2013 23:23 :: mohanpatil :: Replies: 7 :: Views: 705
First let me state that I am not familiar with ST MCU's.
With that said there are several issues with driving the POWERKEY from a MCU as follows.
The POWERKEY should be driven by a open collector (drain) output of a external transistor.
You can however drive it from a MCU pin if the pin can be configured for open drain output
Digital communication :: 03.02.2013 08:19 :: Batang :: Replies: 1 :: Views: 329
Hi guys.i'm new in edaboard :)
I'm in designing car AVL with sim908 module.I have a problem with power unit.The system powered with two power sources,external power from car and the other is internal 3.7 Li-Ion battery.The sim908 has a built-in battery charger(Very Cool!).I want to connect the battery to VBAT pin and external voltage from switchin
Digital communication :: 02.02.2013 10:48 :: SDM(ix) :: Replies: 3 :: Views: 890
I used before already the sim900 and it worked fine.
So I used nearly the same circuit for the sim908 but the netlight is on all the time and nothing happens.
I checked already the powersupply and the ground and everything is fine. I get even an output from 0.35 Volt on the sim908 netlight output pin, but it never changes.
Vbat and vbat2 ha
Microcontrollers :: 15.02.2013 14:51 :: GrinderFX :: Replies: 0 :: Views: 248
Hmmmm, it's your design project but you want others to do all the work.
I don't see how you will learn anything this way.
Anyway here is a link that will make it come true for you:
Digital communication :: 26.02.2013 12:50 :: Batang :: Replies: 2 :: Views: 962
I am using sim908 for my application and i am capturing data from gps antenna and i want it in mode 0 ,
......................................................... but i am not getting proper data that is gps data is lilke something 0,0.000000,0.000000,0.000000,2........................................... and so on...
Professional Hardware and Electronics Design :: 10.03.2013 03:58 :: mohanpatil :: Replies: 1 :: Views: 386
Look at the schematic from the link you poster. The power pin for the sim908 is pin3. It's driven by a transistor(open collector) , which you have to drive high to turn on.
The transistor is going to pin1.
Analog Circuit Design :: 18.03.2013 01:59 :: neddie :: Replies: 4 :: Views: 752
After power on of sim908-C, The simcard_VCC should have 3V which is supplied to sim card. But it is 0V. I did not connect sim908-C(serially) with MCU so far. When i checked DTR and DCD, it's showing high(2.8V). But, DTR in sim908 modem is input pin.
How can DTR have 2.8V without connecting to MCU?(DTR line is to be controlled by MCU (...)
Microcontrollers :: 22.03.2013 07:52 :: Karthik_d :: Replies: 6 :: Views: 567
I am currently working on a project using sim908 and I am facing issue with FTP command, I m trying to get files that is already on the server using "AT+FTPGET=1" but I get time out error " +FTPGET:1,64"
can anyone help ? below the AT commands sequence
Microcontrollers :: 22.03.2013 10:01 :: wael911t :: Replies: 0 :: Views: 498
I am facing one problem communication port of sim908 is connected to xmc controller but sometimes the garbage data is received from uart of controller which is in connection with sim908 i also checked commands , string termination but still i am facing that problem some time .
Please if anybody have the idea about how to solve thi
Microcontrollers :: 24.03.2013 04:39 :: mohanpatil :: Replies: 3 :: Views: 321
Post your circuit. It is related to Power. Did you try sending the command to sim908 from PC or from a microcontroller?
Microcontrollers :: 29.03.2013 10:13 :: jayanth.devarayanadurga :: Replies: 9 :: Views: 690
I' working on sim908 for a couple of days. The GPRS is working fine. At first the GPS module also worked good.
But now when I power ON the GPS module and send "AT+CGPSRST=0" to start it in coldstart mode it gives me OK response but it didn't start in that mode. And the RST is still high.
Maybe thats the reason I'm not getting my location. If a
Digital communication :: 10.04.2013 07:50 :: farhan882 :: Replies: 0 :: Views: 185
What do you mean by sim908 Circuit Diagram.
You have not buy the kit and just the sim908 Module.
Have a look at this page and download the file from the bottom
Software Links :: 14.04.2013 02:18 :: xpress_embedo :: Replies: 4 :: Views: 74
I'm using the sim908 module with an Arduino shield.
But, I don't know why, there is a wrong baudrate setting and the library, of Arduino, say:
Trying to force the baud-rate to 9600
but don't work.
1 week ago it worked, now no, with the same sketch. I haven't change the baudrate with AT commands.
So, there i
Microcontrollers :: 19.04.2013 10:09 :: anerDev :: Replies: 0 :: Views: 259
Im using the sim908 module to obtain GPRS connectivity and a PIC16f877A to obtain the image through UART from the TTL camera module. Image comes through UART and it is 512 bits.
Can anyone please guide me, as to how to send this image through MMS to another place? no exact method.. just a guidance would be so much appreciated.
Microcontrollers :: 22.04.2013 22:08 :: Amalinda :: Replies: 2 :: Views: 354
i am working on sim908 but i am facing problems related on the power the sim908 is not working plz help if any one know
Software Problems, Hints and Reviews :: 14.05.2013 08:37 :: asim_123 :: Replies: 2 :: Views: 274
I m using sim908 for a tracking device. Though sim908 has a GPS module, I still want to know the GSM co-ordinate of the device (As it can be found in SIM900 using AT CIPGSMLOC). Please suggest.
Microcontrollers :: 20.05.2013 02:18 :: Rahul_Patel :: Replies: 1 :: Views: 240
I am using sim908. I need to get GPS data and send it over GPRS. Since my size is very small, I have to use smallest possible antenna. My GSM and GPRS are working fine, but for GPS I am struggling.
I have on board AH316M157501 from Taiyo Yuden for GPS. Since this is chip antenna, I have kept GPS_VANT_IN and GPS_VANT_OUT floating. I am getting
Microcontrollers :: 22.05.2013 08:38 :: mihirDG8 :: Replies: 5 :: Views: 686
I am make boar read longgitude and lattitude from sim908 by PIC 16f887 and show on LCD.
I simulated on Protues it ran ok,
But when test on boar it didn't run.
I don't understand why does it's run
thanks a lot!!
This program on PIC:
Microcontrollers :: 23.05.2013 14:16 :: KaitooKid :: Replies: 1 :: Views: 244
I have an active GSM and GPS antenna of gain 9 and 2.5 respectively.
I want to connect these to the sim908 as I am now in the PCB designing stage in Eagle.
How do I connect these two to the sim908? I understand that I need to connect pin 59,79 the GSM and GPS antenna pins to the respective middle pin. But then, Since both my antennas require powe
PLD, SPLD, GAL, CPLD, FPGA Design :: 09.06.2013 21:15 :: Amalinda :: Replies: 2 :: Views: 309
I want to connect more than one sim to my sim908 but I understand its not possible to directly do so.
Instead I wish to control the SIM-VDD voltage keeping everything else (data,clk,i/o) the same. when I want to shift the network, I will shut down the sim908 and before I switch it back on using my microcontroller, I will apply the VDD to a diffe
Microcontrollers :: 11.06.2013 07:26 :: Amalinda :: Replies: 4 :: Views: 335
I have checked the link you posted for learning sim908 for learning GSM/GPRS/GPS... , I think it is a good one It has got lots of modules and most interestingly two separated UART cable to connect GSM signal and GPS signal respectively to your PC.
Give it a try and post all you learn for community to
Microcontrollers :: 16.06.2013 06:48 :: ultrabrains :: Replies: 11 :: Views: 784
I understand that sim908 does not accept active antennas. Can someone please recomend me a guidance circuit or a method to amplify weak GSM signal in a forest?
Embedded Systems and Real-Time OS :: 15.06.2013 23:02 :: Amalinda :: Replies: 0 :: Views: 279