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[[Image:CPC 472 es.jpg|thumb|right|200px|Spanish Amstrad CPC 472]] The CPC 472 was a spanish version of the CPC [[464|464]] with additional (nonfunctional) 8 KB RAM.  == Description ==

The 8KB extra memory, was a 4164 DRAM chip (64Kx1bit). The DRAMs 1bit databus didn't suit too well to the Z80s 8bit bus, moreover, the daughterboard didn't receive /RAS and /CAS signals which are usually required for DRAM addressing & DRAM refresh. So, even if it would have been functional, the RAM could have been only accessed via complicated software mechanisms; like loading the address LSBs into IR register, and then INning from address MSBs. Because there was no space for a new chip, Amstrad designers took off one of the ROM chips, and put it in a daughter board, along with the 4164 chip. Wires connected pins at the ROM from the daughter board to the corresponding pins on the main board. The wires were hard enough to make difficult to turn the daughter board over and reveal the trick: no wires were connected from the DRAM chip to the main board. Even the supply pins were not connected!!