qdec.h

Low-level QDEC peripheral driver interface definitions.

QDEC_DEV( x)

Default QDEC access macro. 

1
(x)
QDEC_UNDEF

Default QDEC undefined value. 

1
(UINT_MAX)
enum qdec_mode_t
QDEC_X1
QDEC_X2
QDEC_X4
unsigned int qdec_t

Default QDEC type definition.

void(* qdec_cb_t()

Signature of event callback functions triggered from interrupts.

Parameters

arg:optional context for the callback

int32_t qdec_init(qdec.h::qdec_t dev, qdec.h::qdec_mode_t mode, qdec.h::qdec_cb_t cb, void * arg)

Initialize a QDEC device.

The QDEC module is based on virtual QDEC devices. The QDEC devices can be configured to run in three modes :

  • X1
  • X2
  • X4 See description above for more details about modes.

On QDEC counter overflow, an interrupt is triggered. The interruption calls the callback defined.

Parameters

dev:QDEC device to initialize
mode:QDEC mode : X1, X2 or X4
cb:Callback on QDEC timer overflow
arg:Callback arguments

Return values

  • error code on error
  • 0 on success
int32_t qdec_read(qdec.h::qdec_t dev)

Read the current value of the given qdec device.

Parameters

dev:the qdec to read the current value from

Return values

  • the qdecs current value
int32_t qdec_read_and_reset(qdec.h::qdec_t dev)

Read the current value of the given qdec device and reset it.

Parameters

dev:the qdec to read the current value from

Return values

  • the qdecs current value
void qdec_start(qdec.h::qdec_t qdec)

Start the given qdec timer.

This function is only needed if the qdec timer was stopped manually before.

Parameters

qdec:the qdec device to start

void qdec_stop(qdec.h::qdec_t qdec)

Stop the given qdec timer.

This will effect all of the timer’s channels.

Parameters

qdec:the qdec device to stop

struct qdec_isr_ctx_t

Default interrupt context entry holding callback and argument.

qdec.h::qdec_cb_t cb

callback executed from qdec interrupt

void * arg

optional argument given to that callback