Component: NEC IR TX/RX 38KHz (Wireless)

Author	Martin Whitlock
Version	1.1
Category	Wireless

NEC IR TX/RX 38KHz component

Sends and receives standard 8-bit-address NEC infrared remote control frames (38kHz carrier). RX is IOC interrupt-driven the project must configure its own both edge interrupt on RxPin calling ProcessEdge().

Detailed description

No detailed description exists yet for this component

Examples

No additional examples

Macro reference

ClearDataDetected

	ClearDataDetected
Resets DataDetected to false so the next new frame or repeat can be detected again.
- VOID	Return

Initialise

	Initialise
Sets up PWM, RX pin and held-detection timer. Call once at startup.
- VOID	Return

IsDataDetected

	IsDataDetected
On-demand: has a new frame or repeat been decoded since the last ClearDataDetected() call?
- BOOL	Return

IsHeld

	IsHeld
On-demand: is the last decoded button still considered held?
- BOOL	Return

IsRepeat

	IsRepeat
On-demand: was the last decoded frame a repeat code rather than a fresh frame?
- BOOL	Return

ProcessEdge

	ProcessEdge
Call on every RxPin edge (both edges). Returns the last decoded value per Mode: 1=Address, 2=Command, 3=both.
- BYTE	Mode
Which decoded value(s) to return: 1=Address only, 2=Command only, 3=both packed as (Address*256)+Command.
- ULONG	Return

TransmitNEC

	TransmitNEC
Sends one standard NEC frame: 8-bit address, 8-bit inverted address, 8-bit command, 8-bit inverted command.
- BYTE	TxAddress
- BYTE	TxCommand
- VOID	Return

Property reference

	Properties
	PWM Connections
	Channel
Selects which PWM channel the component is connected to.
	Alternative pin
Allows an alternate pin to be used if available. Note that on some devices you will also have to change this setting in the device configuration.
	PWM Pin
Specifies the pin assigned to the PWM channel selected
	Remap Pin
Allows the PWM hardware pin to be reassigned to another pin
	PWM Frequency
	PWM Timer
Timer associated with PWM to drive the output. Warning - All PWM channels linked to the same timer will share the same period and prescaler settings. Do not select Timer 4 - it is used internally by this component for held-button/repeat detection and picking it here will cause a compile error.
	Period Overflow
Allows the user to change the number of counts for the whole PWM period. Note that all PWM channels based on the same timer will share the same period overflow. PIC/AVR Range: 0 - 255 16-bit PIC Range: 0 - 65535
	Prescaler
Allows the user to change the number of program cycles per PWM cycle count. Note that all PWM channels based on the same timer will share the same prescaler.
	Period (us)
Displays the length of time to complete one PWM cycle.
	Frequency (Hz)
	Frequency (KHz)
Displays the frequency of PWM cycles per second.
	Transmit Options
	Invert Output (PNP driver)
Enable if the IR LED is driven through an inverting stage (e.g. a PNP transistor).
	Calculations
	Required Frequency (Hz)
Type in your required frequency in Hz and the component will automatically calculate the best prescaler and period to acheive the frequency with the maximum possible resolution.
	Calculated Frequency (Hz)
The frequency we have ended up acheiving using the calculated period and prescaler
	Calculated Period
The suggested period setting to use to acheive the calculated frequency.
	Calculated Prescaler
The suggested prescaler setting to use to acheive the calculated frequency.
	Apply To Defaults
Applies the calculated period and prescaler settings to the PWM component default settings.
	RX Timer
	Timer
Timer Peripheral to use to monitor the passage of time.
	Bit Depth
Number of bits in the timer peripheral. 8-bit timers can count from 0-255 before overflowing. 16-bit timers can count from 0 to 65535 before overflowing.
	Prescaler
Scaler applied to the timer, Small scalers allow for finer resolution but will limit the max time and also put more load on the microcontroller. Recommended to use as large a setting as possible which still provides enough accuracy.
	RX Pin
Digital input pin connected to the IR receiver module output (active-low: idle=1, mark=0). The embedding project must configure its own both-edge IOC interrupt on this pin calling ProcessEdge().
	Held Threshold (ms)
How long with no repeat before IsHeld() reports released.
	Estimated Best Period (us)
Read-only: the real tick period these Timer/Prescaler/Bit Depth settings achieve. Copy this (rounded) into Tick Period (us).
	Tick Period (us)
Read-only: auto-set from Estimated Best Period whenever RX Timer settings change.
	Diagnostics Enabled
Flags LastRxState/Working* as diagnostic values to read (e.g. over UART) when debugging.

Component Source Code

Please click here to download the component source project: FC_Comp_Source_NEC_IR.fcfx

Please click here to view the component source code (Beta): FC_Comp_Source_NEC_IR.fcfx