merge in some other changes from work

init_sample.py

@@ -3,6 +3,7 @@ class PrintHWInfo:
         #Basic script to print module family, variant, and IP address
         from network import WLAN as wlan, STA_IF as staif
         from time import sleep_ms
+        #TODO support LCD and ePaper displays here
         if hw.features.display.oled:
             oled = hw.oled.handle
             oled.text("uPyConfig!",0,0)

main.py

@@ -38,3 +38,15 @@ sleep_ms(40)
 tft.fill(tft.PURPLE)
 sleep_ms(40)
 tft.fill(tft.WHITE)
+sleep_ms(800)
+
+from fonts import terminal
+from network import WLAN as wlan, STA_IF as staif
+
+print(hw.family)
+print(hw.variant)
+print(wlan(staif).ifconfig()[0])
+
+tft.text((4,4),hw.family,terminal.data)
+tft.text((4,14),hw.variant,terminal.data)
+tft.text((4,24),wlan(staif).ifconfig()[0],terminal.data)

uPaper.py

@@ -0,0 +1,73 @@
+import framebuf
+
+class fbuf(framebuf.FrameBuffer):
+  filled=0
+  clear=1
+  def __init__(self, width, height):
+    self.width=width
+    self.height=height
+    self.buffer=bytearray(width*height//8)
+    super().__init__(self.buffer, width, height, framebuf.MONO_HLSB)
+    self.fill(self.clear)
+
+class epaper:
+  def __init__(self, width, height, refresh_delay=7800, pin_mosi=23, pin_miso=19, pin_sck=18, pin_cs=2, pin_dc=4, pin_rst=0, pin_busy=15, spi_device=2):
+    self.width=width
+    self.height=height
+    self.refresh_delay=refresh_delay
+    self.black=fbuf(width, height)
+    self.red=fbuf(width, height)
+    from epaper1in54b import EPD
+    from machine import Pin, SPI
+    self.mosi=Pin(pin_mosi)
+    self.miso=Pin(pin_miso)
+    self.sck=Pin(pin_sck)
+    self.cs=Pin(pin_cs)
+    self.dc=Pin(pin_dc)
+    self.rst=Pin(pin_rst)
+    self.busy=Pin(pin_rst)
+    self.spi=SPI(spi_device,baudrate=200000,polarity=0,phase=0,mosi=self.mosi,miso=self.miso,sck=self.sck)
+    self.epd=EPD(self.spi,cs=self.cs,dc=self.dc,rst=self.rst,busy=self.busy)
+    #only needs to be run once upon startup, unless the display is placed into low-power mode
+    #using epd.sleep(), then you need to run either epd.init() or epd.reset()
+    self.epd.init()
+
+  def show(self):
+    #reset() appears not to put the display into a state where it will accept new input
+    self.epd.init()
+    self.epd.display_frame(self.black.buffer, self.red.buffer)
+    #display_frame returns as soon as data is sent to the display and the refresh has been initiated
+    #so if we immediately sleep(), the display is never refreshed
+    #thus we wait 7 seconds (manufacturer specified redraw time)
+    self.sleep_ms(self.refresh_delay)
+    self.epd.sleep()
+  
+  def sleep_ms(self, time):
+    from time import sleep_ms
+    sleep_ms(time)
+
+#confusingly, a 1 (interpreted in the display as 0xff) is the "off", or "empty" state for the pixel
+#whereas a 0 is the "on", or "filled" state
+
+#set up framebuffers and backing buffers
+#because we have a display with three colours (red, white, black), this is presented logically
+#as two separate monochrome "frames" of equal size
+#so when rendering, the display_frame function will take as many frames as there are non-white colours
+#this could be used for easy inversion by just swapping the order of arguments to display_frame(buf,buf)
+#some documentation suggests that framebuffer should be initialised directly
+#using FrameBuffer(bytearray(size..))
+#however this causes problems when trying to use the fb as a buffer
+#because it is not "subscriptable"
+#thus the underlying buffer MUST be separated, as it cannot be directly read from inside the fb
+
+#set up SPI, then set up the ePaper display
+#i'm using a WaveShare ePaper SPI 1.54in. display model (B) with a third colour (red)
+#this example code will work identically for the model (C) with yellow as its third colour
+#but is easily adaptable for other waveshare displays  
+#TODO make this configurable
+#SPI is one of the more poorly documented parts of the micropython esp32 port
+#i wish i could make this prettier
+
+#for power saving niceness, we reset before drawing, and sleep afterwards.
+#result of this is that the display may redden a bit but will draw less power
+#TODO figure out if there's a way to have the display only redraw the red or black, at present it redraws both