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LED objects are external hardware mimics.

A LED object changes colour when a logic 0, 1 or high impedance is applied to it. LEDs are normally connected (via WIRE objects) to the OUTPUT objects of a CPU or the XPUT objects of some other object such as an I2C object.

During the interactive design debug phase, when the simulated CPU writes to an I/O port that is connected to a LED object, the LED object will change colour to show the value of the signal sent to it.

	red    indicates 0
	green  indicates 1
	orange indicates high inpedance
The colour actually shown will depend on the value of all inputs to the LED object. If only one output is connected to a LED object and that OUTPUT object changes to an INPUT object, the LED object will receive a high impedance signal which will cause it to change colour to ORANGE.

LED objects are NOT dependent on a running simulator. They are also useful when constructing a hardware console to drive embedded systems. In this case the LED acts as an interactive mimic for a fully functional target system.

Code Generation

The LED object has no user accessable code generation properties associated with it. No code is generated for it. It is only used as a hardware mimic.

Adding LED objects to a design

Normally the LED object is copied from the template window to the drawing window or from an existing LED object already on the drawing window.

Related Information

INPUT objects
OUTPUT objects
WIRE objects
SWITCH objects