XTMax – Teensy 4.1 Hat - 8-bit Software-Defined ISA card - RAM & DISK Functions

The first feature of XTMax is that it can expand the motherboard’s conventional (motherboard) ram up to 640 KB without limitation and with zero wait states. It can expand “conventional” motherboard RAM up to 640 KB, adds up to 16 MB of Expanded RAM, supports 320 KB of UMB RAM, and provides bootable hard-drive access using a MicroSD card.

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