Add free RAM print and quiet() function.

README.md

@@ -311,7 +311,8 @@ gc.collect()  # Precaution before instantiating framebuf
 # Instantiate display and assign to ssd. For args see display drivers doc.
 ssd = SSD(spi, pcs, pdc, prst, usd=True)
 
-from gui.core.ugui import Display, setup
+from gui.core.ugui import Display, quiet
+# quiet()
 # Define control buttons
 nxt = Pin(19, Pin.IN, Pin.PULL_UP)  # Move to next control
 sel = Pin(16, Pin.IN, Pin.PULL_UP)  # Operate current control
@@ -330,6 +331,9 @@ The final arg specifies the sensitivity of the attached encoder, the higher the
 value the more the knob has to be turned for a desired effect. A value of 1
 provides the highest sensitivity, being the native rate of the encoder.
 
+The commented-out `quiet()` line provides a means of suppressing diagnostic
+messages.
+
 Instantiation of `SSD` and `Display` classes is detailed in
 [section 3](./README.md#3-the-ssd-and-display-objects).
 
@@ -390,6 +394,9 @@ Once again, directory structure must be maintained. An example directory
 structure, pruned to contain a minimum of files, may be seen
 [here](https://github.com/peterhinch/micropython-nano-gui#4-esp8266).
 
+For reasons that are unclear, freezing the display driver can lead to
+instability. For this reason it is recommended to freeze the gui tree only.
+
 ###### [Contents](./README.md#0-contents)
 
 ## 1.8 Performance and hardware notes

gui/core/ugui.py

@@ -17,6 +17,7 @@ from gui.primitives import Pushbutton
 # Globally available singleton objects
 display = None  # Singleton instance
 ssd = None
+_vb = True
 
 gc.collect()
 __version__ = (0, 1, 5)
@@ -34,12 +35,15 @@ _NEXT = const(1)
 _PREV = const(2)
 _LAST = const(3)
 
+def quiet():
+    global _vb
+    _vb = False
+
 # Input abstracts input from 2-5 pushbuttons or 3 buttons + encoder. Handles
 # transitions between modes (normal, precision, adjustment)
 class Input:
 
     def __init__(self, nxt, sel, prev, incr, decr, encoder):
-        verbose = True
         self._encoder = encoder  # Encoder in use
         self._precision = False  # Precision mode
         self._adj = False  # Adjustment mode
@@ -60,13 +64,13 @@ class Input:
             self._prev = Pushbutton(prev)
             self._prev.press_func(Screen.ctrl_move, (_PREV,))
         if encoder:
-            verbose and print('Using encoder.')
+            _vb and print('Using encoder.')
             if incr is None or decr is None:
                 raise ValueError('Must specify pins for encoder.')
             from gui.primitives.encoder import Encoder
             self._enc = Encoder(incr, decr, div=encoder, callback=Screen.adjust)
         else:
-            verbose and print('Using {:d} switches.'.format(self._nb))
+            _vb and print('Using {:d} switches.'.format(self._nb))
             # incr and decr methods get the button as an arg.
             if incr is not None:
                 sup = Pushbutton(incr)
@@ -499,11 +503,14 @@ class Screen:
         self.tasks.append((task, on_change))
 
     async def _garbage_collect(self):
+        n = 0
         while True:
             await asyncio.sleep_ms(500)
             gc.collect()
             gc.threshold(gc.mem_free() // 4 + gc.mem_alloc())
-            # print(gc.mem_free())
+            n += 1
+            n &= 0x1f
+            _vb and (not n) and print("Free RAM", gc.mem_free())
 
 # Very basic window class. Cuts a rectangular hole in a screen on which
 # content may be drawn.

hardware_setup.py

@@ -43,7 +43,8 @@ spi = SPI(0, baudrate=30_000_000)
 gc.collect()  # Precaution before instantiating framebuf
 ssd = SSD(spi, pcs, pdc, prst, usd=True)
 
-from gui.core.ugui import Display
+from gui.core.ugui import Display, quiet
+# quiet()
 # Create and export a Display instance
 # Define control buttons
 nxt = Pin(19, Pin.IN, Pin.PULL_UP)  # Move to next control
@@ -51,5 +52,5 @@ sel = Pin(16, Pin.IN, Pin.PULL_UP)  # Operate current control
 prev = Pin(18, Pin.IN, Pin.PULL_UP)  # Move to previous control
 increase = Pin(20, Pin.IN, Pin.PULL_UP)  # Increase control's value
 decrease = Pin(17, Pin.IN, Pin.PULL_UP)  # Decrease control's value
-display = Display(ssd, nxt, sel, prev)  # 3-button mode
+# display = Display(ssd, nxt, sel, prev)  # 3-button mode
-# display = Display(ssd, nxt, sel, prev, increase, decrease, 5)  # Encoder mode
+display = Display(ssd, nxt, sel, prev, increase, decrease, 5)  # Encoder mode