diff --git a/display.py b/display.py
index 582f61c..eb338d9 100644
--- a/display.py
+++ b/display.py
@@ -1,12 +1,15 @@
 import asyncio
 from LCD import LCD
 
+alloc_lock = asyncio.Lock()
+
 class display:
     def __init__(self, width=20, height=4, i2c_addr=0x27):
         self.width = width
         self.height = height
         self.device = LCD(2, i2c_addr, True)
         self.contents = [" " * width] * self.height
+        self.custom_char_allocations = [False] * 8
     
     async def redraw(self, row = None):
         if row == None:
@@ -15,6 +18,15 @@ class display:
         else:
             await self.device.async_message(self.contents[row - 1], row)
     
+    async def alloc_cchar(self):
+        async with alloc_lock:
+            new_alloc = self.custom_char_allocations.index(False)
+            self.custom_char_allocations[new_alloc] = True
+        return new_alloc
+        
+    async def free_cchar(self, cchar):
+        self.custom_char_allocations[cchar] = False
+    
     async def read(self, row):
         return self.contents[row]
     
diff --git a/kladd/pins.txt b/kladd/pins.txt
index bf7f45b..b8be684 100644
--- a/kladd/pins.txt
+++ b/kladd/pins.txt
@@ -7,3 +7,7 @@ GPIO pins:
 2, 3: display
 
 23, 24: misc buttons
+
+5, 6: aux serial (5 is pi->pc)
+
+12: fan pwm
\ No newline at end of file