Debug problem in 18f452 communication with SIM300

Hi, Have a Great Day. I can help you. i made the remote datalogger using SIM300 and AVR ATMEGA16. The first problem i faced was malfunctioning of the MODEM. It has following reasons in hardware as well as software. The Hardware issues: 1. The current supplied by the Power supply is insuffecient. 2. The Modem Works with 4.2V (probably) and it is required to insert 2 diodes in series with VCC and MODEM battery line. 3. You don't need to put MAX in between MCU and SIM300 (when MODEM is transmitting the SMS it consumes 2000m Amp current, this results in mal functioning of the MAX232/MAX233). 4. Thermal Isues have to be cattered. Software Issues: 1. There is minimum delay of 1msec between each command e.g (AT; delay(1 milli sec);). 2. The serial buffer must be kept empty before and after transmitting the commands. 3. It is good practice to send AT command before expiring of sleep time. i hope this will help in fixing up the issues. The bottle neck for me is PIC microcontroller (i havn't programmed the PIC). if you require any help please feel free to contact. Best Regards, Shahbaz.

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Hello I can help you find the error in your design. I have 4 years experience with SIM and GPS devices I have 8 years of product design in the automotive industry. Also I am an expert in: - Dc - Dc converters - USB charging - accelerometers, gyroscopes - GPS and GSM - LCD Displays - LED power calculation As a plus I have work before with ARM procesor("ARM11") As a Layou-er I have 5 Years experience. I am an expert in: - Power Dissipation Calculation - EMC Rules - Impedance Calculation - Manufacturing Rules I have made Layout for ARM processor. Work also with BGA footprint. I have done projects even on 10 layer. So I know how to build a layer stack up. As Layout and Schematic software I am an expert in Eagle, PADs, Zuken. As Simulation software for the Schematic I used LTSpice. If you want more information feel free to contact me.

Hi, I've worked with SIM300 and other SIMCom modules. I've extensive experience in interfacing SimCom modules with mcu as well as developing firmware for the same. I can help you fix the issue with your current h/w and s/w. The quoted cost is for: 1. Identifying and fixing any h/w and s/w issues in current setup. 2. Adding support for Temp sensor, SMS based on-off and Batt voltage detection. I would require schematics of your current design and the firmware code. Which micro-controller you are using? I understand you design is patented and I'll respect that, hence assure you that I will not disclose any IP of this project. Let me know when we can start. I am ready for the job. Regards, Polestar

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Hello...Im Electrical-Electronics engneer...I have experience Embedded systems programing(PIC,MSP,ARDUNIO) and PCB layout works...If you contact with me i can send you my portofilio and work details things... my name Cengiz Demir Whatsapp: 0090 533 237 2616

i have done projects based on SIM 300 and SIM 900 and have a sound knowledge of AT command which are used to communicate with SIM 300 and MCU. I can do this task in less than 2 days and you will not be dissatisfied by my work.

I have an expert in pic programming and i have done lots of project using pic with SIM 300. I have done projects used SMS(receive and transmit) and Analog monitoring (temperature monitoring and humidity etc).

Hello, I can do that. You can see last project my follow in the portfolio. You can direct communication with the module without MAX232, use the resistor communication. The sample on my portfolio.

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I already developed advanced vehicle tracking system on M95 Quectel module and SIM900 with advanced functionality. I can easily suggest hardware changes and also provide some proven functionality of my source code.

I have already deal with this problem, data is not received by microcontroller. Solution is very simple, SIM300 is very fast in communication and PIC 18f452 can't handle such a high clock speed. So need to place a buffer IC between these two components. In this way both can communication with each other. I have a vast experience on PCB layout design on Eagle CAD. I can also provide you the PCB lay out of working project with no extra charge. There is no need of MAX 232 for this as you mentioned. Power supply is also an important parameter SIM300 has surge peek current of 2A, so low current power supply can't be used. If required power supply layout can b provided on extra charge. For coding I use MikroC PRO, code for PIC 18F452 can be provided after hardware verified by you. Because software code is totally depend on hardware configurations. I use Real Time Operating System which give you better response time and multitasking if required, otherwise single loop coding is also can be provide on demand. If you have working code then it will not required to be change because your problem is hardware based.