display: Add ST7567 display support (#1540)

Signed-off-by: Dmitry Budaev <condemil@gmail.com>

config/example-extras.cfg

@@ -1221,9 +1221,14 @@
 #a0_pin:
 #   The pins connected to an uc1701 type lcd. These parameters must be
 #   provided when using an uc1701 display.
-#contrast: 40
-#   The contrast to set when using a uc1701 type display.  The value may
-#   range from 0 to 63.  Default is 40.
+#rs_pin:
+#cs_pin:
+#a0_pin:
+#   The pins connected to an st7567 type lcd. These parameters must be
+#   provided when using an st7567 display.
+#contrast:
+#   The contrast to set when using a uc1701/st7567 type displays.  The value
+#   may range from 0 to 63. Default is 40 for uc1701 and 60 for st7567.
 #cs_pin:
 #dc_pin:
 #spi_bus:

klippy/extras/display/display.py

@@ -12,6 +12,7 @@ import menu
 LCD_chips = {
     'st7920': st7920.ST7920, 'hd44780': hd44780.HD44780,
     'uc1701': uc1701.UC1701, 'ssd1306': uc1701.SSD1306,
+    'st7567': uc1701.ST7567,
 }
 M73_TIMEOUT = 5.
 

klippy/extras/display/uc1701.py

@@ -2,6 +2,7 @@
 #
 # Copyright (C) 2018  Kevin O'Connor <kevin@koconnor.net>
 # Copyright (C) 2018  Eric Callahan  <arksine.code@gmail.com>
+# Copyright (C) 2019  Dmitry Budaev <condemil@gmail.com>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import logging
@@ -178,6 +179,39 @@ class UC1701(DisplayBase):
         self.flush()
         logging.info("uc1701 initialized")
 
+# The ST7567 is a "4-wire" SPI display device
+class ST7567(DisplayBase):
+    def __init__(self, config):
+        DisplayBase.__init__(self, SPI4wire(config, "a0_pin"))
+        self.contrast = config.getint('contrast', 60, minval=0, maxval=63)
+        ppins = config.get_printer().lookup_object('pins')
+        rs_pin = config.get('rs_pin')
+        self.reset_pin = ppins.setup_pin('digital_out', rs_pin)
+        self.reset_pin.setup_start_value(start_value=1., shutdown_value=0.,
+                                         is_static=False)
+    def init(self):
+        # Send init commands
+        init_cmds = [0xE2, # System reset
+                     0x40, # Set display to start at line 0
+                     0xA0, # Set SEG direction
+                     0xC8, # Set COM Direction
+                     0xA2, # Set Bias = 1/9
+                     0x2F, # Boost, regulator, follower on
+                     0xF8, # Set booster ratio
+                     0x00, # Booster ratio value (4x)
+                     0x23, # Set regulation ratio (3)
+                     0x81, # Set Electronic Volume
+                     self.contrast, # Electronic Volume value
+                     # 0xAC, # Set static indicator off
+                     # 0x00, # NOP
+                     0xA6, # Disable Inverse
+                     0xAF] # Set display enable
+        self.send(init_cmds)
+        self.send([0xA5]) # display all
+        self.send([0xA4]) # normal display
+        self.flush()
+        logging.info("st7567 initialized")
+
 # The SSD1306 supports both i2c and "4-wire" spi
 class SSD1306(DisplayBase):
     def __init__(self, config):