Ignition System for Fireworks Display

Figure 1 

The goal of creating the fireworks ignition system is to provide control over 30 unique channels which can switch the power source ON and OFF by using a transistor circuit in each channel.

An SX48 is the main part of the circuit which runs at 50MHz. There are 36 I/O pins available in the SX48 which makes it possible to dedicate 30 lines to the 30 channels. A line will be connected to a 7805 where the state of the arming key is monitored while the serial port control will have 2 lines connected to a MAX233 chip. To communicate with the PIC A/D converter through an SPI interface, the 3 remaining lines are used, making all the SX’s lines fully used.

A 12V 1.3Ah sealed lead acid battery is used to power the system or a DC input jack mounted which allows recharging through a wall wart is used in place of the battery. As a safety mechanism, an arming key was included where no power is applied to the transistor when unarmed. A serial port set at 38.4kbps is used as the control of the system, allowing the setting of channels.

Rest of the project