Changes

C't 512 KB internal RAM expansion

143 bytes added, 11:58, 7 May 2010
/* Components */
16x 41256 (256Kx1 DRAM) ;replacing the CPC6128's 16 built-in 64Kx1 DRAMs
1x PAL 16L8 ;replacing the CPC6128's built-in PAL
1x 74LS38 ( ;Quad 2-input NAND, OC) 1x 74LS273 ( ;8bit latch, of which only 6bit 5bit are used here) 1x 2200 Ohm resistor ;pull-up for OC output 1x 470 Ohm resistor ;pull-up for OC output 1x 47 Ohm resistor ;purpose unknown (noise related? shortcut protection?)
* '''DRAM Replacement''' - Replace the sixteen old 64Kx1 DRAM chips by new 256Kx1 DRAMs. The chips have same pinouts, only pin 1 is changed (old: NC, new: A8 row:column address signal).
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