Badger2040W: Use partial update for seconds on clock

micropython/examples/badger2040w/examples/clock.py

@@ -5,7 +5,7 @@ import badger2040w
 
 
 display = badger2040w.Badger2040W()
-display.set_update_speed(3)
+display.set_update_speed(2)
 display.set_thickness(4)
 
 WIDTH, HEIGHT = display.get_bounds()
@@ -14,7 +14,7 @@ try:
     display.connect()
     if display.isconnected():
         ntptime.settime()
-except RuntimeError:
+except (RuntimeError, OSError):
     pass  # no WiFI
 
 rtc = machine.RTC()
@@ -23,6 +23,8 @@ display.set_font("gothic")
 
 
 def draw_clock():
+    global second_offset, second_unit_offset
+
     hms = "{:02}:{:02}:{:02}".format(hour, minute, second)
     ymd = "{:04}/{:02}/{:02}".format(year, month, day)
 
@@ -39,7 +41,35 @@ def draw_clock():
     display.text(hms, hms_offset, 40, 0, 1.8)
     display.text(ymd, ymd_offset, 100, 0, 1.0)
 
+    display.set_update_speed(2)
     display.update()
+    display.set_update_speed(3)
+
+    hms = "{:02}:{:02}:".format(hour, minute)
+    second_offset = hms_offset + display.measure_text(hms, 1.8)
+    hms = "{:02}:{:02}:{}".format(hour, minute, second // 10)
+    second_unit_offset = hms_offset + display.measure_text(hms, 1.8)
+
+
+def draw_second():
+    global second_offset, second_unit_offset
+
+    display.set_pen(15)
+    display.rectangle(second_offset, 8, 75, 56)
+    display.set_pen(0)
+
+    if second // 10 != last_second // 10:
+        s = "{:02}".format(second)
+        display.text(s, second_offset, 40, 0, 1.8)
+        display.partial_update(second_offset, 8, 75, 56)
+
+        s = "{}".format(second // 10)
+        second_unit_offset = second_offset + display.measure_text(s, 1.8)
+
+    else:
+        s = "{}".format(second % 10)
+        display.text(s, second_unit_offset, 40, 0, 1.8)
+        display.partial_update(second_unit_offset, 8, 75 - (second_unit_offset - second_offset), 56)
 
 
 year, month, day, wd, hour, minute, second, _ = rtc.datetime()
@@ -48,11 +78,17 @@ if (year, month, day) == (2021, 1, 1):
     rtc.datetime((2022, 2, 28, 0, 12, 0, 0, 0))
 
 last_second = second
+last_minute = minute
+draw_clock()
 
 
 while True:
     year, month, day, wd, hour, minute, second, _ = rtc.datetime()
     if second != last_second:
-        draw_clock()
+        if minute != last_minute:
+            draw_clock()
+            last_minute = minute
+        else:
+            draw_second()
         last_second = second
     time.sleep(0.01)