Initial M5Stack Cardputer support

Author: RetiredWizard

cpython/cardputer/lib/adafruit_debouncer.mpy

@@ -0,0 +1,162 @@
+"""
+`M5StackCardputerKbd`
+====================================================
+
+CircuitPython M5Stack Cardputer Matrix Keyboard driver.
+
+* Author(s): foamyguy during YouTube livestream
+             https://www.youtube.com/watch?v=la7g24fP7IQ&t=4s
+
+             retiredwizard added modifier keys (shift, alt, ...) and minor performance changes
+
+"""
+
+
+import board
+import digitalio
+import keypad
+from adafruit_debouncer import Debouncer
+#import time
+
+class MultiplexerKeys():
+
+    def __init__(self,multiplexed_row_pins, column_pins, value_when_pressed=False):
+        self.row_pins = multiplexed_row_pins
+        self.column_pins = column_pins
+        self.row_dio_objs = []
+        self.col_dio_objs = []
+        
+        # Initialize the row pins as outputs
+        for row_pin in self.row_pins:
+            _cur_dio = digitalio.DigitalInOut(row_pin)
+            _cur_dio.direction = digitalio.Direction.OUTPUT
+            self.row_dio_objs.append(_cur_dio)
+            
+        # Initialize the colun pins as inputs with pull-ups
+        for column_pin in self.column_pins:
+            _cur_dio = digitalio.DigitalInOut(column_pin)
+            _cur_dio.direction = digitalio.Direction.INPUT
+            _cur_dio.pull = digitalio.Pull.UP
+            self.col_dio_objs.append(Debouncer(_cur_dio,.1))
+#            self.col_dio_objs.append(_cur_dio)
+        
+        self.value_when_pressed = value_when_pressed
+        
+        self._events = []
+        self._last_key = None
+        
+    @property
+    def events(self):
+        self._scan()
+        return self._events
+    
+# Function to scan the key matrix
+    def _scan(self):
+        self._events = []
+        key_num = -1   # Set so held button can be differentiated from no key pressed
+        for i in range(8):
+            self.set_multiplexer_state(i)
+            for col, column_pin in enumerate(self.col_dio_objs):
+                column_pin.update()
+                column_pin.update()
+                while column_pin.state not in [0,3]:
+                    column_pin.update()
+                if column_pin.value == self.value_when_pressed:  # If a key is pressed
+                    key_num = (i * len(self.col_dio_objs)) + col
+                    #print("Key ({}, {:03b}, {}) pressed".format(key_num, i, col))
+                    self._events.append(keypad.Event(key_number=key_num, pressed=True))
+                    self._last_key = key_num
+#                    time.sleep(.1)
+        if key_num == -1:    # No keys pressed
+            if self._last_key is not None:
+                self._events.append(keypad.Event(key_number=self._last_key, pressed=False))
+                self._last_key = None
+#                time.sleep(.1)
+
+    def set_multiplexer_state(self, state_binary):
+        for idx, compare in enumerate((0b100,0b010,0b001)):
+            self.row_dio_objs[idx].value = True if state_binary & compare else False
+    
+class Cardputer():
+    def __init__(self):
+        row_pins = (board.KB_A_0, board.KB_A_1, board.KB_A_2)
+        column_pins = (
+            board.KB_COL_0, board.KB_COL_1, board.KB_COL_2, board.KB_COL_3, board.KB_COL_4, board.KB_COL_5, board.KB_COL_6)
+
+        self._KEY_MATRIX_LUT = [
+            # row 4
+            ("OPT","",""), ("z","Z",""), ("c","C",""), ("b","B",""),
+            ("m","M",""), (".",">","DOWN"), (" ","",""), ("CTRL","",""),
+            ("ALT","",""), ("x","X",""), ("v","V",""), ("n","N",""),
+            (",","<","LEFT"), ("/","?","RIGHT"),
+            
+            # row 2
+            ("q","Q",""), ("e","E",""), ("t","T",""), ("u","U",""),
+            ("o","O",""), ("[","{",""), ("\\","|",""), ("\t","",""), 
+            ("w","W",""), ("r","R",""), ("y","Y",""), ("i","I",""),
+            ("p","P",""), ("]","}",""),
+            
+            # row 3
+            ("SHIFT","",""), ("s","S",""), ("f","F",""), ("h","H",""),
+            ("k","K",""), (";",":","UP"), ("\n","",""), ("FN","",""),
+            ("a","A",""), ("d","D",""), ("g","G",""), ("j","J",""),
+            ("l","L",""), ("'",'"',""),
+            
+            # row 1
+            ("1","!",""), ("3","#",""), ("5","%",""), ("7","&",""),
+            ("9","(",""), ("_","-",""), ("\x08","",""), ("`","~","\x1b"),
+            ("2","@",""), ("4","$",""), ("6","^",""), ("8","*",""),
+            ("0",")",""), ("=","+","")
+        ]
+        
+        self.keyboard = MultiplexerKeys(row_pins, column_pins)
+        
+        self.shift = False
+        self.funct = False
+        self.ctrl = False
+        self.opt = False
+        self.alt = False
+        
+    def check_keyboard(self):
+        events = self.keyboard.events
+        new_char_buffer = ""
+        if events:
+            for event in events:
+                if event.pressed:
+                    new_char = self._KEY_MATRIX_LUT[event.key_number][0]
+                    if new_char in ['SHIFT','FN','CTRL','OPT','ALT']:
+                        new_char = ""
+                    else:
+                        if self.shift:
+                            new_char = self._KEY_MATRIX_LUT[event.key_number][1]
+                            self.shift = False
+                        elif self.funct:
+                            new_char = self._KEY_MATRIX_LUT[event.key_number][2]
+                            self.funct = False
+                        #new_char_buffer += new_char    # Replaced so only last char if multiple events
+                        new_char_buffer = new_char      # (multiple keys simultaneously pressed)
+                        
+                else:
+                # For modifer keys disable auto-repeat by only responding to "RELEASE" events
+                    new_char = self._KEY_MATRIX_LUT[event.key_number][0]
+                    if new_char == "SHIFT":
+                        self.shift = not self.shift
+                    elif new_char == "FN":
+                        self.funct = not self.funct
+                    elif new_char == "CTRL":
+                        self.ctrl = not self.ctrl
+                    elif new_char == "OPT":
+                        self.opt = not self.opt
+                    elif new_char == "ALT":
+                        self.alt = not self.alt
+                    
+
+        return new_char_buffer
+
+# Exmple Usage:
+#
+#cardputer = Cardputer()
+
+#while True:
+#    print(cardputer.check_keyboard(),end="")
+