hd44780: Use two separate text framebuffers

There is concern that some lcd boards that emulate the hd44780 don't
support text updates that wrap the two text framebuffers.  Update the
code to treat the two text areas as two separate framebuffers.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 10 insertions, 9 deletions

diff --git a/klippy/extras/display/hd44780.py b/klippy/extras/display/hd44780.py
index 7a56720b..77fd3b40 100644
--- a/klippy/extras/display/hd44780.py
+++ b/klippy/extras/display/hd44780.py
@@ -28,11 +28,12 @@ class HD44780:
         self.mcu.register_config_callback(self.build_config)
         self.send_data_cmd = self.send_cmds_cmd = None
         # framebuffers
-        self.text_framebuffer = bytearray(' '*80)
+        self.text_framebuffers = [bytearray(' '*40), bytearray(' '*40)]
         self.glyph_framebuffer = bytearray(64)
         self.all_framebuffers = [
-            # Text framebuffer
-            (self.text_framebuffer, bytearray('~'*80), 0x80),
+            # Text framebuffers
+            (self.text_framebuffers[0], bytearray('~'*40), 0x80),
+            (self.text_framebuffers[1], bytearray('~'*40), 0xc0),
             # Glyph framebuffer
             (self.glyph_framebuffer, bytearray('~'*64), 0x40) ]
     def build_config(self):
@@ -71,8 +72,6 @@ class HD44780:
             # Transmit changes
             for pos, count in diffs:
                 chip_pos = pos
-                if fb_id == 0x80 and pos >= 40:
-                    chip_pos += 0x40 - 40
                 self.send([fb_id + chip_pos])
                 self.send(new_data[pos:pos+count], is_data=True)
             old_data[:] = new_data
@@ -89,13 +88,13 @@ class HD44780:
         # Add custom fonts
         self.glyph_framebuffer[:len(HD44780_chars)] = HD44780_chars
         for i in range(len(self.glyph_framebuffer)):
-            self.all_framebuffers[1][1][i] = self.glyph_framebuffer[i] ^ 1
+            self.all_framebuffers[2][1][i] = self.glyph_framebuffer[i] ^ 1
         self.flush()
     def write_text(self, x, y, data):
         if x + len(data) > 20:
             data = data[:20 - min(x, 20)]
-        pos = [0, 40, 20, 60][y] + x
-        self.text_framebuffer[pos:pos+len(data)] = data
+        pos = x + ((y & 0x02) >> 1) * 20
+        self.text_framebuffers[y & 1][pos:pos+len(data)] = data
     def write_glyph(self, x, y, glyph_name):
         char = TextGlyphs.get(glyph_name)
         if char is not None:
@@ -104,7 +103,9 @@ class HD44780:
             return 1
         return 0
     def clear(self):
-        self.text_framebuffer[:] = ' '*80
+        spaces = ' ' * 40
+        self.text_framebuffers[0][:] = spaces
+        self.text_framebuffers[1][:] = spaces
     def get_dimensions(self):
         return (20, 4)