Regarding the RAM remapping: There was Didaktik Gama (made by the same company, that made D40), that had 80kB RAM. It was done by switching the 32768-65535 addr

Regarding the RAM remapping: There was Didaktik Gama (made by the same company, that made D40), that had 80kB RAM. It was done by switching the 32768-65535 address range between two banks.