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/*
* This file is subject to the terms of the GFX License. If a copy of
* the license was not distributed with this file, you can obtain one at:
*
* http://ugfx.org/license.html
*/
#include "gfx.h"
#if GFX_USE_GINPUT && GINPUT_NEED_MOUSE
#define GMOUSE_DRIVER_VMT GMOUSEVMT_MAX11802
#include "../../../../src/ginput/ginput_driver_mouse.h"
// Hardware definitions
#include "max11802.h"
// Get the hardware interface
#include "gmouse_lld_MAX11802_board.h"
// Register values to set
#define MAX11802_MODE 0x0E // Direct conversion with averaging
#define MAX11802_AVG 0x55
#define MAX11802_TIMING 0x77
#define MAX11802_DELAY 0x55
#define Z_MIN 0
#define Z_MAX 1
static gBool MouseInit(GMouse* m, unsigned driverinstance)
{
const uint8_t *p;
static const uint8_t commandList[] = {
MAX11802_CMD_GEN_WR, 0xf0, // General config - leave TIRQ enabled, even though we ignore it ATM
MAX11802_CMD_RES_WR, 0x00, // A-D resolution, hardware config - rewriting default; all 12-bit resolution
MAX11802_CMD_AVG_WR, MAX11802_AVG, // A-D averaging - 8 samples, average four median samples
MAX11802_CMD_SAMPLE_WR, 0x00, // A-D sample time - use default
MAX11802_CMD_TIMING_WR, MAX11802_TIMING, // Setup timing
MAX11802_CMD_DELAY_WR, MAX11802_DELAY, // Conversion delays
MAX11802_CMD_TDPULL_WR, 0x00, // A-D resolution, hardware config - rewrite default
// MAX11802_CMD_MDTIM_WR, 0x00, // Autonomous mode timing - write default - only for MAX11800, MAX11801
// MAX11802_CMD_APCONF_WR, 0x00, // Aperture config register - rewrite default - only for MAX11800, MAX11801
// Ignore aux config register - not used
MAX11802_CMD_MODE_WR, MAX11802_MODE // Set mode last
};
if (!init_board(m, driverinstance))
return gFalse;
aquire_bus(m);
for (p = commandList; p < commandList+sizeof(commandList); p += 2)
write_command(m, p[0], p[1]);
release_bus(m); // Need to release bus after each access to reset interface in chip
// (and in some cases, to allow sharing of SPI bus if board logic/OS manages it)
// Setup complete here
// Read something as a test
aquire_bus(m);
if (write_command(m, MAX11802_CMD_MODE_RD, 0) != MAX11802_MODE) {
release_bus(m);
return gFalse;
}
release_bus(m);
return gTrue;
}
static gBool read_xyz(GMouse* m, GMouseReading* pdr)
{
uint8_t readyCount;
uint8_t notReadyCount;
// Assume not touched.
pdr->buttons = 0;
pdr->z = 0;
aquire_bus(m);
// Start the conversion
gfintWriteCommand(m, MAX11802_CMD_MEASUREXY); // just write command
release_bus(m);
/**
* put a delay in here, since conversion will take a finite time - longer if we were reading Z as well
* Potentially at least 1msec for 3 axes with 8us conversion time per sample, 8 samples per average
* Note Maxim AN5435-software to do calculation (www.maximintegrated.com/design/tools/appnotes/5435/AN5435-software.zip)
*
* We'll just use a fixed delay to avoid too much polling/bus activity
*/
gfxSleepMilliseconds(2); // Was 1 - try 2
/* Wait for data ready
* Note: MAX11802 signals the readiness of the results using the lowest 4 bits of the result. However, these are the
* last bits to be read out of the device. It is possible for the hardware value to change in the middle of the read,
* causing the analog value to still be invalid even though the tags indicate a valid result.
*
* We work around this by reading the registers once more after the tags indicate they are ready.
* There's also a separate counter to guard against never getting valid readings.
*
* Read the two readings required in a single burst, swapping x and y order if necessary
*
* Reading Z is possible but complicated requiring two z readings, multiplication and division, various constant ratio's,
* and interpolation in relation to the X and Y readings. It is not a simple pressure reading.
* In other words, don't bother trying.
*/
readyCount = notReadyCount = 0;
do {
// Get a set of readings
aquire_bus(m);
gfintWriteCommand(m, MAX11802_CMD_XPOSITION);
#if defined(GINPUT_MOUSE_YX_INVERTED) && GINPUT_MOUSE_YX_INVERTED
pdr->y = read_value(m);
pdr->x = read_value(m);
#else
pdr->x = read_value(m);
pdr->y = read_value(m);
#endif
release_bus(m);
// Test the result validity
if (((pdr->x | pdr->y) & 0x03) == 0x03) {
// Has it been too long? If so give up
if (++notReadyCount >= 5) {
return gFalse;
}
// Give up the time slice to someone else and then try again
gfxYield();
continue;
}
// We have a result but we need two valid results to believe it
readyCount++;
} while (readyCount < 2);
/**
* format of each value returned by MAX11802:
* Bits 15..4 - analog value
* Bits 3..2 - tag value - measurement type (X, Y, Z1, Z2)
* Bits 1..0 - tag value - event type (00 = valid touch, 10 - no touch, 11 - measurement in progress)
*/
// Was there a valid touch?
if (((pdr->x | pdr->y) & 0x03) != 0x0) {
pdr->z = Z_MIN;
return gTrue;
}
// Strip the tags (we need to take care because coord_t is signed - and sign bit gets extended on shift!)
pdr->x = (uint16_t)(pdr->x) >> 4;
pdr->y = (uint16_t)(pdr->y) >> 4;
pdr->z = Z_MAX;
return gTrue;
}
const GMouseVMT const GMOUSE_DRIVER_VMT[1] = {{
{
GDRIVER_TYPE_TOUCH,
GMOUSE_VFLG_TOUCH | GMOUSE_VFLG_ONLY_DOWN | GMOUSE_VFLG_POORUPDOWN | GMOUSE_VFLG_CALIBRATE | GMOUSE_VFLG_CAL_TEST,
sizeof(GMouse) + GMOUSE_MAX11802_BOARD_DATA_SIZE,
_gmouseInitDriver,
_gmousePostInitDriver,
_gmouseDeInitDriver
},
Z_MAX, // z_max
Z_MIN, // z_min
Z_MAX, // z_touchon
Z_MIN, // z_touchoff
{ // pen_jitter
GMOUSE_MAX11802_PEN_CALIBRATE_ERROR, // calibrate
GMOUSE_MAX11802_PEN_CLICK_ERROR, // click
GMOUSE_MAX11802_PEN_MOVE_ERROR // move
},
{ // finger_jitter
GMOUSE_MAX11802_FINGER_CALIBRATE_ERROR, // calibrate
GMOUSE_MAX11802_FINGER_CLICK_ERROR, // click
GMOUSE_MAX11802_FINGER_MOVE_ERROR // move
},
MouseInit, // init
0, // deinit
read_xyz, // get
0, // calsave
0 // calload
}};
#endif /* GFX_USE_GINPUT && GINPUT_NEED_MOUSE */
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