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Rewrite of the MCU driver. This is now much more reliable.

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This commit is contained in:
inmarket 2013-11-24 02:23:21 +10:00
parent e87ba59d8d
commit 361136d7ca
1 changed files with 39 additions and 39 deletions
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78
drivers/ginput/touch/MCU/ginput_lld_mouse.c
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@ -24,7 +24,6 @@
#include "ginput_lld_mouse_board.h"
static uint16_t sampleBuf[7];
static coord_t lastx, lasty;
/**
* @brief 7-point median filtering code for touchscreen samples
@ -63,56 +62,57 @@ void ginput_lld_mouse_init(void) {
*
* @param[in] pt A pointer to the structure to fill
*
* @note For drivers that don't support returning a position
* when the touch is up (most touch devices), it should
* return the previous position with the new Z value.
* The z value is the pressure for those touch devices
* that support it (-100 to 100 where > 0 is touched)
* or, 0 or 100 for those drivers that don't.
* @note We use a 7 sample medium filter on each coordinate to remove analogue noise.
* @note During touch transition the ADC can return some very strange
* results. To fix this behaviour we don't return until
* we have tested the touch is in the same state at both the beginning
* and the end of the reading.
* @note Whilst x and y can return readings in any range so long as it fits in 16 bits,
* the z value must be ranged by the board file to be a rough percentage. Anything
* greater than 80% pressure is a touch.
*
* @notapi
*/
void ginput_lld_mouse_get_reading(MouseReading *pt) {
uint16_t i;
// If touch-off return the previous results
if (!getpin_pressed()) {
pt->x = lastx;
pt->y = lasty;
pt->z = 0;
pt->buttons = 0;
return;
}
// Read the port to get the touch settings
// Obtain access to the bus
aquire_bus();
/* Get the X value
* Discard the first conversion - very noisy and keep the ADC on hereafter
* till we are done with the sampling.
* Once we have the readings, find the medium using our filter function
*/
read_x_value();
for(i = 0; i < 7; i++)
sampleBuf[i] = read_x_value();
filter();
lastx = (coord_t)sampleBuf[3];
// Read the ADC for z, x, y and then z again
while(1) {
setup_z();
for(i = 0; i < 7; i++)
sampleBuf[i] = read_z();
filter();
pt->z = (coord_t)sampleBuf[3];
/* Get the Y value using the same process as above */
read_y_value();
for(i = 0; i < 7; i++)
sampleBuf[i] = read_y_value();
filter();
lasty = (coord_t)sampleBuf[3];
setup_x();
for(i = 0; i < 7; i++)
sampleBuf[i] = read_x();
filter();
pt->x = (coord_t)sampleBuf[3];
setup_y();
for(i = 0; i < 7; i++)
sampleBuf[i] = read_y();
filter();
pt->y = (coord_t)sampleBuf[3];
pt->buttons = pt->z >= 80 ? GINPUT_TOUCH_PRESSED : 0;
setup_z();
for(i = 0; i < 7; i++)
sampleBuf[i] = read_z();
filter();
i = (coord_t)sampleBuf[3] >= 80 ? GINPUT_TOUCH_PRESSED : 0;
if (pt->buttons == i)
break;
}
// Release the bus
release_bus();
// Return the results
pt->x = lastx;
pt->y = lasty;
pt->z = 100;
pt->buttons = GINPUT_TOUCH_PRESSED;
}
#endif /* GFX_USE_GINPUT && GINPUT_NEED_MOUSE */