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Hi Tramp,
I have designed the modem as per the schematics in ver2.0, previously I neglected to groung body. If you tell me your problem I can suggest you.
Added after 1 minutes:
Hi Tramp,
I have designed the modem as per the schematics in ver2.0, previously I neglected to groung body. If you tell me your problem I can suggest you.
Hi Tramp,
I have designed the modem as per the schematics in ver2.0, previously I neglected to groung body. If you tell me your problem I can suggest you.
Hi gravi,
Thanks for your reply.I have attached interfacing circuit herewith.Problem observed that it get power on properly,but not get registered to network even though there is simcard (6 pin simcard holder) & antenna.also it is observed that Simvdd Pin does'nt go high(2.8V)after putting simcard.
I advise you to replace C4 with a 100uF/10V (at least), low esr type. On the PCB, make sure the traces between C4 and module pins are short and thick. The module may fail to register if you have high amplitude spikes on vdd pin during emission, check this with a scope and attach a capture if you can. This problem may occur if you have a poor quality antenna (high VSWR).
Hi Tramp,
Design your module as per the data sheet's I'm attaching be very carefull with ground,s and don't forgot to ground body. Use power on circuit from page 6 difference between sim300 and sim100 pdf.
Hi everybody
Im transmitting data packets(nearly 500Bites) to host through GPRS, unfortunately some of my packets are missing.
Modem responds SEND OK after a packet is sent. Im not getting any responce for those missing packets. In data sheet it is mensioned that Modem responds either SEND OK/SEND FAIL or ERROR but Im not getting any kind of response for missed packets. I havent used flow control's. Is flow control manditory at 9600kbps baud rate.
According to my hardware RTS is pulled down and CTS and DTR are Not connect.
I have been partially satisfied working with Sim300 fine.
1. I would like to know is there any command to reset modem.
2. Is it manditory to switch On modem manually when modem Switches OFF due to low power (less than 3.4 V).
Hi,
Iam also having the problem of no SIMVDD. although I am getting the poweron and LED blinking. Does it realyy related to the baudrate, what if I have not connected to PC at all
Added after 11 minutes:
Hi,
For Sim300, Does it really require the full rs 232 link or can i work only with Rx,Tx RTS and CTS for normal operation with at commands ( not considering the s/w upgradation)
Hi all, I have just purchased a SIM300 module for under $85 in Bnaglore, India.
I am unable to find any sort of documentation on it.
I am in desperate need of interfacing diagrams.
Please help!
Hi
You can find all the datasheets required for SIM300 under the same POST and RX and Tx lines are sufficient to interface with your controller and you need to maintain same power supply for modem and Controller (same voltage).
I have SIM399-EVB_v2.02 board which works fine.
But know I placed the design on our board and conected it to ARM7 procesor, which for know I am not using full Modem interface( I connected DTR an RTS to 0 ) , and currently just configured RX and TX pins.
And I have the same problem as described before. I just receive 64ms and 800ms led blink periode.
could be UART reason for problems?
I am attaching v 1.06 design used for building my project
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