diff --git a/README.md b/README.md index 9757249..37de240 100644 --- a/README.md +++ b/README.md @@ -3090,26 +3090,40 @@ connecting to any host. The hardware_setup.py should be copied or adapted from `setup_examples/pico_epaper_42_pico.py`. If using the socket, default args may be used (see code comment). -After an initial refresh to clear the screen the driver is put into partial -mode. This provides a reasonably quick and visually satisfactory response to -user inputs such as button events. See the +Some attention to detail is required to handle the refresh characteristics. +The application must wait for the initial full refresh (which occurs +automatically) before putting the display into partial mode. This is done by +the screen constructor issuing +```python + asyncio.create_task(set_partial()) +``` +to run +```python +async def set_partial(): # Ensure 1st refresh is a full refresh + await Screen.rfsh_done.wait() # Wait for first refresh to end + ssd.set_partial() +``` +The application then runs in partial mode with a reasonably quick and visually +satisfactory response to user inputs such as button events. See the [epaper demo](https://github.com/peterhinch/micropython-micro-gui/blob/main/gui/demos/epaper.py). -This provides for a full refresh via the `reset` button. Provision of full -refresh is application dependent. It should be done as follows: +It is likely that applications will provide a full refresh method to clear any +ghosting. The demo provides for a full refresh via the `reset` button. A full +refresh should be done as follows: ```python async def full_refresh(): Screen.rfsh_done.clear() # Enable completion flag await Screen.rfsh_done.wait() # Wait for a refresh to end ssd.set_full() - Screen.rfsh_done.clear() # Enable completion flag + Screen.rfsh_done.clear() # Re-enable completion flag await Screen.rfsh_done.wait() # Wait for a single full refresh to end - ssd.set_partial() + ssd.set_partial() # Subsequent refreshes are partial ``` - The driver for the supported display uses 1-bit color mapping: this means that greying-out has no visible effect. Greyed-out controls cannot accept the focus -and are therefore disabled but appearance is unchanged. +and are therefore disabled but appearance is unchanged. `nano-gui` has a 2-bit +driver which supports greyscales, but there is no partial support so this is +unsuitable for `micro_gui`. ###### [Contents](./README.md#0-contents) diff --git a/gui/demos/epaper.py b/gui/demos/epaper.py index be3ff50..d038214 100644 --- a/gui/demos/epaper.py +++ b/gui/demos/epaper.py @@ -47,6 +47,9 @@ async def full_refresh(): await Screen.rfsh_done.wait() # Wait for a single full refresh to end ssd.set_partial() +async def set_partial(): # Ensure 1st refresh is a full refresh + await Screen.rfsh_done.wait() # Wait for first refresh to end + ssd.set_partial() class FooScreen(Screen): def __init__(self): @@ -161,6 +164,7 @@ class FooScreen(Screen): Label(wri_large, lbl.mrow + 5, col, "y = sinc(x)") CloseButton(wri, bgcolor=BLACK) + asyncio.create_task(set_partial()) # After 1st full refresh asyncio.create_task(run(dial, lbltim, m0, scale)) def callback(self, button, buttons, val): @@ -186,7 +190,6 @@ class FooScreen(Screen): x += 0.05 Curve(self.graph, None, populate()) - asyncio.create_task(full_refresh()) async def run(dial, lbltim, m0, scale): diff --git a/setup_examples/pico_epaper_42_pico.py b/setup_examples/pico_epaper_42_pico.py index b648a5b..3ab80da 100644 --- a/setup_examples/pico_epaper_42_pico.py +++ b/setup_examples/pico_epaper_42_pico.py @@ -56,4 +56,3 @@ 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, increase, decrease) # 5-button mode ssd.wait_until_ready() # Blocking wait -ssd.set_partial() # Subsequent refreshes are partial