Generic (but slow) Serial Driver using an LED instead of TX and RX wires. More...

Functions
void	ldInit (void)
	LEDComm Driver initialization. More...

void	ldObjectInit (LEDCommDriver_t *ldp, qnotify_t inotify, qnotify_t onotify)
	Initializes a generic full duplex driver object. More...

void	ldStart (LEDCommDriver_t ldp, const LEDCommConfig_t config)
	Configures and starts the driver. More...

void	ldStop (LEDCommDriver_t *ldp)
	Stops the driver. More...

void	ldIncomingDataI (LEDCommDriver_t *ldp, uint8_t b)
	Handles incoming data. More...

msg_t	ldRequestDataI (LEDCommDriver_t *ldp)
	Handles outgoing data. More...

LEDComm status flags
#define	LD_PARITY_ERROR 32
	Parity error happened. More...

#define	LD_FRAMING_ERROR 64
	Framing error happened. More...

#define	LD_OVERRUN_ERROR 128
	Overflow happened. More...

#define	LD_LINK_UP 256
	Link detected. More...

#define	LD_LINK_DOWN 512
	No link detected. More...

Detailed Description

Generic (but slow) Serial Driver using an LED instead of TX and RX wires.

This module implements a generic half duplex serial driver that uses an LED instead of TX and RX wires. The driver implements a SerialDriver interface and uses I/O Queues for communication. Event flags are used to notify the application about incoming data, outgoing data and other I/O events.

Precondition: In order to use the LEDComm driver the source code must be extracted in the $(CHIBIOS)/ext directory. The project Makefile must be modified by adding $(CHIBIOS)/ext/ledcomm-X.Y.Z/ledcomm.c to the CSRC variable and $(CHIBIOS)/ext/ledcomm-X.Y.Z to the INCDIR variable.

Driver State Machine

The driver implements a state machine internally, not all the driver functionalities can be used in any moment, any transition not explicitly shown in the following diagram has to be considered an error and shall be captured by an assertion (if enabled).

Macro Definition Documentation

#define LD_PARITY_ERROR 32

Parity error happened.

Definition at line 54 of file ledcomm.h.

#define LD_FRAMING_ERROR 64

Framing error happened.

Definition at line 55 of file ledcomm.h.

#define LD_OVERRUN_ERROR 128

Overflow happened.

Definition at line 56 of file ledcomm.h.

Referenced by ldIncomingDataI().

#define LD_LINK_UP 256

Link detected.

Definition at line 57 of file ledcomm.h.

#define LD_LINK_DOWN 512

No link detected.

Definition at line 58 of file ledcomm.h.

Function Documentation

void ldInit ( void )

LEDComm Driver initialization.

Note: This function is NOT implicitly invoked by halInit(), you must explicitly initialize the driver.

Function Class:: Initializer, this function just initializes an object and can be invoked before the kernel is initialized.

Definition at line 296 of file ledcomm.c.

References ldObjectInit().

Here is the call graph for this function:

void ldObjectInit	(	LEDCommDriver_t *	ldp,
		qnotify_t	inotify,
		qnotify_t	onotify
	)

Initializes a generic full duplex driver object.

The HW dependent part of the initialization has to be performed outside, usually in the hardware initialization code.

Parameters

[out]	ldp	pointer to a `LEDCommDriver` structure
[in]	inotify	pointer to a callback function that is invoked when some data is read from the Queue. The value can be `NULL`.
[in]	onotify	pointer to a callback function that is invoked when some data is written in the Queue. The value can be `NULL`.

Function Class:: Initializer, this function just initializes an object and can be invoked before the kernel is initialized.

Definition at line 322 of file ledcomm.c.

References LD_STOP, LEDCOMM_BUFFERS_SIZE, and LEDCommDriver::vmt.

Referenced by ldInit().

void ldStart	(	LEDCommDriver_t *	ldp,
		const LEDCommConfig_t *	config
	)

Configures and starts the driver.

Parameters

[in]	ldp	pointer to a `LEDCommDriver` object
[in]	config	the architecture-dependent LEDComm driver configuration. If this parameter is set to `NULL` then a default configuration is used.

Function Class:: Normal API, this function can be invoked by regular system threads but not from within a lock zone.

Definition at line 341 of file ledcomm.c.

References LEDCommConfig_t::anode_pad, LEDCommConfig_t::anode_port, LEDCommConfig_t::cathode_extmode, LEDCommConfig_t::cathode_pad, LEDCommConfig_t::cathode_port, LEDCommConfig_t::data_bits, LD_READY, LD_STOP, LEDCOMM_DATA_BITS7, LEDCOMM_DEFAULT_SYNCS, and LEDCommConfig_t::threshold.

void ldStop ( LEDCommDriver_t * ldp )

Stops the driver.

Any thread waiting on the driver's queues will be awakened with the message Q_RESET.

Parameters

[in] ldp pointer to a LEDCommDriver object

Function Class:: Normal API, this function can be invoked by regular system threads but not from within a lock zone.

Definition at line 413 of file ledcomm.c.

References LD_READY, and LD_STOP.

void ldIncomingDataI	(	LEDCommDriver_t *	ldp,
		uint8_t	b
	)

Handles incoming data.

This function must be called from the input interrupt service routine in order to enqueue incoming data and generate the related events.

Note: The incoming data event is only generated when the input queue becomes non-empty.; In order to gain some performance it is suggested to not use this function directly but copy this code directly into the interrupt service routine.

Parameters

[in]	ldp	pointer to a `LEDCommDriver` structure
[in]	b	the byte to be written in the driver's Input Queue

Function Class:: This is an I-Class API, this function can be invoked from within a system lock zone by both threads and interrupt handlers.

Definition at line 445 of file ledcomm.c.

References LD_OVERRUN_ERROR.

msg_t ldRequestDataI ( LEDCommDriver_t * ldp )

Handles outgoing data.

Must be called from the output interrupt service routine in order to get the next byte to be transmitted.

Note: In order to gain some performance it is suggested to not use this function directly but copy this code directly into the interrupt service routine.

Parameters

[in] ldp pointer to a LEDCommDriver structure

Returns: The byte value read from the driver's output queue.

Return values

Q_EMPTY if the queue is empty (the lower driver usually disables the interrupt source when this happens).

Function Class:: This is an I-Class API, this function can be invoked from within a system lock zone by both threads and interrupt handlers.

Definition at line 474 of file ledcomm.c.

Functions

LEDComm status flags

Detailed Description

Driver State Machine

Macro Definition Documentation

Function Documentation