.. label for cross-referencing
.. _250469:

######
250469
######

* PCB ASSY NO. 250469
* Schematic Number #252312
* Released in 1987
* 8-pin board (CN5-Video port has 8 pins)
* KERNAL & BASIC ROMS combined into U4
* New IC memory controller U8
* This highly redesigned motherboard is commonly known as a “short board”
* The “short board” used the new HMOS-chipset, featuring a new 64-pin PLA chip. The new “SuperPLA”, as it was dubbed, integrated many discrete components and Transistor–Transistor Logic (TTL) chips.
* In the last revision of the C64C motherboard, the 2114 color RAM was integrated into the SuperPLA.


=====================
Components' placement
=====================

.. rst-class:: components-placement

+----------------+----------------------------------------------------+--------------------------+---------------------+
| PCB Identifier | IC number                                          | IC type                  | Memory location/bit |
+================+====================================================+==========================+=====================+
| U1             | :ref:`6526 <6526>`                                 | CIA 1                    | $DC00-$DCFF         |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U2             | :ref:`6526 <6526>`                                 | CIA 2                    | $DD00-$DDFF         |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U3             | 74LS08                                             |                          | N/A                 |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U4             | 23128                                              | BASIC and KERNAL ROM     | | $A000-$BFFF       |
|                |                                                    |                          | | $E000-$FFFF       |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U5             | 2332                                               | CHARACTER ROM            | $D000-$DFFF         |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U6             | :ref:`8500 <8500>`                                 | CPU                      | N/A                 |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U7             | :ref:`8562 <8562>` (NTSC)/:ref:`8565 <8565>` (PAL) | VIC-II                   | $D000-$D3FF         |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U8             | | :ref:`251715 <251715>` (Rev.A, Rev.3, Rev.4)     | PLA                      | N/A                 |
|                | | :ref:`252535 <252535>` (Rev.B)                   |                          |                     |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U9             | :ref:`8580 <8580>`                                 | SID                      | $D400-$D7FF         |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U10            | :ref:`41464 <41464>`                               | DRAM 64K x 4             | D0-D3               |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U11            | :ref:`41464 <41464>`                               | DRAM 64K x 4             | D4-D7               |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U18            | 4066                                               | Quad Bilateral Switch    | N/A                 |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U19            | :ref:`2114 <2114>` (not on Rev.B)                  | SRAM 1K x 4              | $D800-$DBFF         |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U20            | :ref:`8701 <8701>`                                 | Oscillator               | N/A                 |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U21            | 4066                                               | Quad Bilateral Switch    | N/A                 |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U22            | 7404                                               | inverter                 | N/A                 |
+----------------+----------------------------------------------------+--------------------------+---------------------+
| U23            | 7404                                               | inverter                 | N/A                 |
+----------------+----------------------------------------------------+--------------------------+---------------------+