23-01-2013, 10:20 AM
28-PIN PROJECT BOARD
[attachment=48090]
Introduction
The 28-pin project board is designed to allow rapid prototyping with
28-pin PICAXE microcontrollers. The board provides connections for
eight digital inputs (inputs portC 0-7), four analogue inputs (inputs
portA 0-3) and eight digital outputs (outputs portB 0-7). Each of the
outputs is driven through a ULN2803A darlington driver, which will drive up to
800mA per output. Ribbon cables with connectors are also included, which enable easy
interfacing to the board. Space is provided on the board for adding an optional motor
driver IC, through which DC motors can be controlled with forward/reverse directional
control.
Power
The board can be powered by a single, or two separate, power supplies. When two power
supplies are used the second separate supply (V2+) is used to power the output devices.
This is useful when a higher voltage is required (e.g. when driving a 12V stepper motor) or
when it is necessary to isolate the outputs to avoid noise problems (e.g. when using radiocontrol
servos).
The primary power supply (V1+) for the interface is a 5V or 4.5V DC. This is connected via
the battery clip connector. DO NOT use a 9V PP3 battery, as the interface does not include
a voltage regulator.
Motor Driver
An optional L293D motor driver IC (not supplied) may be added to the basic interface.
This provides forward-backward control of two DC motors, controlled by outputs 4 to 7.
Naturally, if only one motor is to be controlled then only two output lines are used.
[attachment=48090]
Introduction
The 28-pin project board is designed to allow rapid prototyping with
28-pin PICAXE microcontrollers. The board provides connections for
eight digital inputs (inputs portC 0-7), four analogue inputs (inputs
portA 0-3) and eight digital outputs (outputs portB 0-7). Each of the
outputs is driven through a ULN2803A darlington driver, which will drive up to
800mA per output. Ribbon cables with connectors are also included, which enable easy
interfacing to the board. Space is provided on the board for adding an optional motor
driver IC, through which DC motors can be controlled with forward/reverse directional
control.
Power
The board can be powered by a single, or two separate, power supplies. When two power
supplies are used the second separate supply (V2+) is used to power the output devices.
This is useful when a higher voltage is required (e.g. when driving a 12V stepper motor) or
when it is necessary to isolate the outputs to avoid noise problems (e.g. when using radiocontrol
servos).
The primary power supply (V1+) for the interface is a 5V or 4.5V DC. This is connected via
the battery clip connector. DO NOT use a 9V PP3 battery, as the interface does not include
a voltage regulator.
Motor Driver
An optional L293D motor driver IC (not supplied) may be added to the basic interface.
This provides forward-backward control of two DC motors, controlled by outputs 4 to 7.
Naturally, if only one motor is to be controlled then only two output lines are used.