Fixed the EEPROM header writing and reading

* Fixes a bug where addresses 0x58-0x5F were being assumed to be
EEPROMs but were not contiguous.
* Fixes some bad assumptions on address length in the writing tools
* Adds templates for the two types of EEPROM officially supported

modules/scripts/prepare_eeprom.py

@@ -18,20 +18,31 @@
 print(f"Detected eeprom at {hex(addr)}")
 
 # Fill in your desired header info here:
-header = HexpansionHeader(
+# use this one for the M24C16:
+header_m24c16 = HexpansionHeader(
     manifest_version="2024",
     fs_offset=32,
     eeprom_page_size=16,
-    eeprom_total_size=2048,
-    vid=0xCAFE,
-    pid=0xD15C,
+    eeprom_total_size=1024 * (16 // 8),
+    vid=0xCA75,
+    pid=0x1337,
+    unique_id=0,
+    friendly_name="M24C16"
+)
+# use this template for the ZD24C64A
+header_zd24c64 = HexpansionHeader(
+    manifest_version="2024",
+    fs_offset=32,
+    eeprom_page_size=32,
+    eeprom_total_size=1024 * (64 // 8),
+    vid=0xCA75,
+    pid=0x1337,
     unique_id=0x0,
-    friendly_name="Flopagon",
+    friendly_name="ZD24C64A",
 )
 
-# Determine amount of bytes in internal address
-#addr_len = 2 if header.eeprom_total_size > 256 else 1
-#print(f"Using {addr_len} bytes for eeprom internal address")
+# pick which one to use here
+header = header_m24c16
 
 # Write and read back header
 write_header(

modules/system/hexpansion/header.py

@@ -97,8 +97,10 @@ def from_bytes(cls, buf, validate_checksum=True):
 def write_header(port, header, addr=0x50, addr_len=2, page_size=32):
     i2c = I2C(port)
 
-    addr_bytes = [0] * addr_len
-    i2c.writeto(addr, bytes(addr_bytes))
+    if addr_len == 2:
+        addr_pack = ">H"
+    else:
+        addr_pack = ">B"
 
     # We can't write more bytes than the page size in one transaction, so chunk the bytes if necessary:
     header_bytes = header.to_bytes()
@@ -107,10 +109,10 @@ def write_header(port, header, addr=0x50, addr_len=2, page_size=32):
     ]
 
     for idx, chunk in enumerate(header_chunks):
-        write_addr = bytes([idx * page_size])
-        print(f"Writing {len(chunk)} bytes at {write_addr}:", chunk)
+        write_addr = struct.pack(addr_pack, idx * page_size)
+        print(f"Writing {len(chunk)} bytes at {idx * page_size}:", chunk)
 
-        i2c.writeto(addr, bytes([idx * page_size]) + chunk)
+        i2c.writeto(addr, write_addr + chunk)
 
         # Poll ACK
         while True:

modules/system/hexpansion/util.py

@@ -65,7 +65,6 @@ def get_hexpansion_block_devices(i2c, header, addr=0x50, addr_len=2):
         i2c=i2c,
         chip_size=chip_size,
         page_size=header.eeprom_page_size,
-        addr=addr,
         block_size=block_size
     )
     partition = EEPROMPartition(