touch driver

CHANGELOG.txt

@@ -1,2 +1,4 @@
+0.2.0
+    - add AD7843 touch panel driver
 0.1.0
     - extract library from Doton project

gfxlcd/demos/touch.py

@@ -1,5 +1,6 @@
 import RPi.GPIO
 import sys
+import time
 sys.path.append("../../")
 from gfxlcd.driver.ili9325.gpio import GPIO as ILIGPIO
 from gfxlcd.driver.ili9325.ili9325 import ILI9325
@@ -7,18 +8,25 @@ from gfxlcd.driver.ad7843.ad7853 import AD7843
 RPi.GPIO.setmode(RPi.GPIO.BCM)
 
 
-# lcd_tft = ILI9325(240, 320, ILIGPIO())
-# lcd_tft.init()
+lcd_tft = ILI9325(240, 320, ILIGPIO())
+lcd_tft.init()
 
 
-touch = AD7843(240, 320)
+def callback(position):
+    print('(x,y)', position)
+
+touch = AD7843(240, 320, 26, callback)
+
+touch.init()
 
 while True:
     try:
-        ret = touch.get_position()
-        if ret:
-            # s.draw_pixel(ret[0], ret[1])
-            print(ret[0], ret[1])
+        time.sleep(0.05)
+        # ret = touch.get_position()
+        # if ret:
+        #     print(ret[0], ret[1])
 
     except KeyboardInterrupt:
         touch.close()
+        # RPi.GPIO.cleanup()
+

gfxlcd/driver/ad7843/ad7853.py

@@ -1,9 +1,10 @@
 import spidev  # pylint: disable=I0011,F0401
+import RPi.GPIO
 
 
 class AD7843(object):
     """AD7843 class"""
-    def __init__(self, width, height, spi=0):
+    def __init__(self, width, height, int_pin=None, callback=None, spi=0):
         self.width = width
         self.height = height
         self.spi = spidev.SpiDev()
@@ -16,6 +17,17 @@ class AD7843(object):
             'ratio_x': 14.35,
             'ratio_y': 10.59
         }
+        self.int_pin = int_pin
+        self.callback = callback
+        self.bouncetime = 500
+
+    def init(self):
+        """some init functions"""
+        if self.int_pin:
+            RPi.GPIO.setup(self.int_pin, RPi.GPIO.IN)
+            RPi.GPIO.add_event_detect(
+                self.int_pin, RPi.GPIO.BOTH, callback=self._interrupt, bouncetime=self.bouncetime
+            )
 
     def get_x(self, value):
         """correct value to x"""
@@ -23,28 +35,31 @@ class AD7843(object):
 
     def get_y(self, value):
         """correct value to y"""
-        return self.height - int((value - self.correction['y']) /  self.correction['ratio_y'])
+        return self.height - int((value - self.correction['y']) / self.correction['ratio_y'])
+
+    def _interrupt(self, channel):
+        """call users callback"""
+        self.callback(self.get_position())
 
     def get_position(self):
         """get touch coords"""
         buffer = []
         while len(buffer) < 20:
             self.spi.xfer2([0xd0])
-            rx = self.spi.readbytes(2)
+            recvx = self.spi.readbytes(2)
             self.spi.xfer2([0x90])
-            ry = self.spi.readbytes(2)
+            recvy = self.spi.readbytes(2)
 
-            tc_rx = rx[0] << 5
-            tc_rx |= rx[1] >> 3
+            tc_rx = recvx[0] << 5
+            tc_rx |= recvx[1] >> 3
 
-            tc_ry = ry[0] << 5
-            tc_ry |= ry[1] >> 3
+            tc_ry = recvy[0] << 5
+            tc_ry |= recvy[1] >> 3
 
-            x = self.get_x(tc_rx)
-            y = self.get_y(tc_ry)
-            if x < 0 or x > self.width or y < 0 or y > self.height:
-                return None
-            buffer.append((x, y))
+            pos_x = self.get_x(tc_rx)
+            pos_y = self.get_y(tc_ry)
+            if  0 <= pos_x <= self.width and 0 <= pos_y <= self.height:
+                buffer.append((pos_x, pos_y))
 
         return self._calculate_avr(buffer)
 
@@ -59,6 +74,8 @@ class AD7843(object):
         return int(sum_x / len(points)), int(sum_y / len(points))
 
     def close(self):
-        """vlose action"""
+        """close action"""
+        if self.int_pin:
+            RPi.GPIO.remove_event_detect(self.int_pin)
         self.spi.close()
 

readme.md

@@ -9,13 +9,18 @@ Supported:
 - ssd1306 via SPI
 - nju6450 via GPIO
 
+And for touch panels:
+
+- ad7843 via SPI, uses irq or not
+
+
 On NJU and SSD uses buffer to keep current content as help for page operations.
 
 Wiring is below
 
 Demos are in demos directory
 
-Initialization
+LCD initialization
 ===
 ## SSD1306
 ### SPI
@@ -125,6 +130,47 @@ lcd.threshold = 255 - for images a threshold between black and white (on monochr
 lcd.transparency_color = [110, 57] #110 - color(s) that are skipped during drawing an image
 
 
+## Touch panels
+===
+
+## AD7843
+
+Constructor:
+    
+    AD7843(width, height, (T_INT), (callback))
+    
+Can be used with T_INT
+
+    def callback(position):
+        print('(x,y)', position)
+    
+    touch = AD7843(240, 320, 26, callback)
+    touch.init()
+
+or without:
+
+    touch = AD7843(240, 320)
+    touch.init()
+
+    while True:
+        try:
+            time.sleep(0.05)
+            ret = touch.get_position()
+            if ret:
+                print(ret[0], ret[1])
+    
+        except KeyboardInterrupt:
+            touch.close()
+
+There is no automatic calibration. It must be done manually.
+         
+    self.correction = {
+        'x': 364,
+        'y': 430,
+        'ratio_x': 14.35,
+        'ratio_y': 10.59
+    }
+             
 Wiring
 ===
 

setup.py

@@ -13,7 +13,7 @@ def read(*paths):
 
 setup(
     name='gfxlcd',
-    version='0.1.2',
+    version='0.2.0',
     description='gfxlcd is a handler for grpahical lcds: ILI9328, SSD1306, NJU6450 @ Raspberry Pi.',
     keywords=['gfxlcd', 'raspberry pi' ,'ili9328' ,'ssd1306', 'nju6450', 'lcd', 'graphical lcd'],
     long_description=(read('readme.md')),