A quick dump of the old BIOS from the Pioneer LaserActive PAC-S1 revealed some issues with the dumping process… I need to inspect my GQ-4X as it seems to have some strange issues going on!

The chip has a sticker over the erase window marked PIONEER PD6126E. Underneath is a Fujitsu MBM27C1024A-12Z, dated to week 28 of 1993. The MBM27C1024A is a 1 Mbit UV-erasable EPROM in a 40-pin package.

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