Almost all game programs require a random number generator. When implementing games for embedded systems, generating random numbers raises certain interesting issues. While generation of random number can be done using the rand() C library function, getting a suitable seed is a challenge.

ZDev is an open source software framework, consisting of modules for easy and quick embedded application development. ZDev is free and open source software, and is distributed under LGPL. ZDev currently supports the following microcontrollers:

The ZKit-51-V664 has a Graphics LCD, that can be used for displaying GUIs, bitmaps, animations, etc. Bitmaps can be easily displayed on the Graphics LCD using the APIs provided by ZDev library. This article shows how to create bitmaps using GIMP, and how to display them on the Graphics LCD.

A GSM modem is a specialised type of modem which accepts a SIM card, and operates over a subscription to a mobile operator, just like a mobile phone. These modems are more frequently connected to computers which allow the computers to communicate with the mobile network. They are most probably used for sending/receiving SMS. This article explains how to connect a GSM modem with the ZKit-51 and how to program it to send SMS.

Resistance is the reluctance or a kind of friction in a carrier which opposes the flow of current through it. The resistance of an element is measurable and it is represented by an unit known as Ohm. Ohmmeter is a device used to measure the electrical resistance. This project shows how to construct a simple ohmmeter using 8051 microcontroller.

It is very easy to generate tones with the ZDev library and the ZKit-51. This project shows how to generate tones of various frequencies using the PWM controller.

Generally Thermometer is used to measure the ambient temperature. This article explains you about how to design a simple Thermometer using a temperature sensor.

In order to test an electronic circuit, we need some testing equipment. Capacitance meter is an electronic equipment used to measure capacitance. This project will show how to construct a simple capacitance meter using 8051 controller.

It may require some graphics image to be displayed in 8051 based products through a monochrome bitmap LCD. This is considered to be a complex task because of its bus interfacing and several command sequence handling. This article explains how a graphics LCD from TIANMA can be connected to a 8051 micro-controller and pixels can be displayed on it with simple steps.

All 8051 based microcontrollers from NXP come with some sort of built-in flash memory. The microcontrollers provide multiple methods to program the flash. The most common method is In-System Programming (ISP). In ISP, the code is transfered to the flash, through the serial port, by a built-in ISP bootloader. The other method is In-Application Programming (IAP). In IAP, the user application receives the code through whatever mechanism (like say SPI or I²C) and programs the flash. A set of built-in routines, called the IAP routines, are available to the application for manipulating the flash.

This article shows how to access the IAP routines on P89V66x based devices. The routines will be accessed from C, and the free and open source SDCC compiler will be used.

There are variety of user input devices for embedded systems, like buttons, switches, knobs, sliders, etc. Sliders are most commonly used for volume controls. This project shows how to interface a slider to the ZKit-51, and how to use it as an input device.

It is necessary to know the stack utilization levels when software is developed for systems requiring high reliability. A simple technique to determine the stack utilization of a program is watermarking. In this technique the stack is filled with a pattern, and the program is executed. When the stack is used the pattern is overwritten. When the program terminates the point from which the pattern is undisturbed tells us the stack utilization level.

BASIC is a very popular programming language taught in schools. There have been various derivatives of the BASIC programming language. The most popular ones are GW-BASIC, QBASIC and Visual Basic. In fact there are versions of BASIC for the 8051 as well, called the MCS BASIC-52.

The MCS BASIC-52, is written in assembly language, and hence is hard to extend. Mordern 8051s have large memories and hence it is possible to implement a BASIC interpreter in C. This article shows how to port a tiny BASIC interpreter to the ZKit-51.

When your projects get bigger, the internal RAM of the P89V664 is no longer sufficient. External RAM can be used to overcome this limitation. The P89V664 used in the ZKit-51 has 2KB of on-chip external RAM.

The external RAM can be used from SDCC, in two ways