Changes
/* Custom Chips */
40015 16K ROM; AMSDOS for CPC664/CPC6128 and DDI-1 disc interface
40022 32K ROM; BIOS and BASIC for CPC664 (English)
40025 32K ROM; BIOS and BASIC for CPC6128 (English)[grimware.org says 40024, not 40025 ?]
40026 PCW8xxx printer controller ASIC
40028 PCW8xxx/9xxx main ASIC
