Hardware used

Microcontroller based device
The device is implemented a microcontroller interfaced with external chips and devices. The program is written either in assembly language or in other high level languages that have compilers available, like the C language.

Hardware Components

•  Atmel^® AT89C52: This is the microcontroller we used. It is based on the 8052 family, including an extra timer, larger internal RAM (256 bytes) and built-in flash memory of 8 KBytes.
• Programmable Peripheral Interface 8255: This is a general purpose programmable I/O device, capable of providing 24 I/O pins.
• Liquid Crystal Display (LCD): This was used as a means of display to the user. It shows the current time, date, prayer times, options …etc. The LCD used is a 2X16 LCD (2 lines X16 character/line).
• Hitachi^® 62256 CMOS SRAM: An external RAM chip was needed to expand the memory capability of the AT89C52 microcontroller. This chip includes 256 Kbits arranged as 32786 X 8 bits.
• 74373 8-bit latch: This octal latch was used to store the values of the address pins A0-A7 that come out of the controller into the 62256 SRAM and 8255 PPI.
• 7404 Hex inverters.
• LM386 Audio Amplifier: This low voltage audio amplifier was used to boost the output of the microcontroller to be able to drive the speaker of the device to sound the alarm.