week 7 ( 24/9/2012 - 28/9/2012)

             For this week activities, i study deeply about on how to interface the signal in the GSM modem from Programmable Interface Circuit (PIC). So, serial communication interface between micro and pc i must put max232 to convert signal from ttl level (micro) to rs232 level (pc). This is the function of max232 level converter. The MAX232 is a dual driver/receiver that includes a capacitive voltage generator to supply TIA/EIA-232-F voltage levels from a single 5-V supply. Each receiver converts TIA/EIA-232-F inputs to 5-V TTL/CMOS levels. These receivers have a typical threshold of 1.3 V, a typical hysteresis of 0.5 V, and can accept ±30-V inputs. Each driver converts TTL/CMOS input levels into TIA/EIA-232-F levels. The driver, receiver, and voltage-generator functions are available as cells in the Texas Instruments LinASIC library.

 

            

                                                                 MAX232 schematic diagram

The RS232 serial port protocol (v.24) states -15v to represent binary 1 and +15v to represent binary 0.  For TTL communication this is incompatible since TTL uses 0v to represent binary 0 and +5v to represent binary 1.  MAX232 chip converts serial signal voltage levels to TTL standards, and also vias versa. It therefore has a driver and a receiver to perform this function.

week 6 (17/9/2012 - 21/9/2012)

         In this week, the next progress schedule for my project is testing and troubleshoot all equipment used using simulation. This method is great way to prevent any possibilities of failure and error during completing the circuit at next semester. The progress needs some helps from any friends who experts in troubleshoot the error that may occur in the simulation. This part is little bit difficult to identify the problems. The progress work that i have done as shown below:

•  Combine the circuit part of project
• Measure the output result
• Compare the result with actual problem
• Fix all the errors

week 5 (10/9/2012 - 14/9/2012)

         In this week, i have discussed with TNB distribution worker about designing the project. All the design  ideas, i have compiled together and finalize that. Both voltage and temperature sensor will connected at distribution cable to detect overvoltage and high temperature condition. The manner that i have done as shown below:

• Create the initial prototype 
• Identify the operation flow
• Collect and record the result simulation data
• Finalize the prototype

week 4 ( 3/9/2012 - 7/9/2012)

                During this period, I finished for the second stage in my project schedule which is been studied and testing the hardware that used for this project. Hardware a basic electronic element that used. There are 4 criteria that i have done for completing the hadware part :

• Identify the equipment used
• Select the suitable project body
• Research the data and information
• Design the circuit

week 3 (27/8/2012 - 31/8/2012)

            In this week, i have been studied the software part by creating the operation for power distribution monitoring using simulation. For software part, there are two types of software that involved for this project that have shown below:

• GSM programming

           The sending SMS through GSM modem when interfaced with microcontroller or PC is much simpler as compared with sending SMS through Modem in PDU Mode.Text message may be sent through the modem by interfacing only three signals of the serial interface of modem with microcontroller i.e.,TxD,RxD and GND.In this scheme RTS and CTS signals of serial port interface of GSM Modem are connected with each other.The transmit signal of serial port of microcontroller is connected with transmit signal (TxD) of the serial interface of GSM Modem while receive signal of microcontroller serial port is connected with receive signal (RxD) of serial interface of GSM Modem.The COMPIM Serial Port Model shown in the schematic diagram developed in Proteus VSM is equivalent to the serial interafce of GSM Modem.

• PIC programming

         Basically , the most suitable and easy to understand the coding flow for project operation is Assembly Languages. A programming language that is once removed from a computer's machine language. Machine languages consist entirely of numbers and are almost impossible for humans to read and write. Assembly languages have the same structure and set of commands as machine languages, but they enable a programmer to use names instead of numbers.

Each type of CPU has its own machine language and assembly language, so an assembly language program written for one type of CPU won't run on another. In the early days of programming, all programs were written in assembly language. Now, most programs are written in a high-level language such as FORTRAN or C. Programmers still use assembly language when speed is essential or when they need to perform an operation that isn't possible in a high-level language.