TRS-80 PC-2 24K RAM Expansion (USB controlled)

Schematic 

     24K RAM expansion module for TRS-80 PC-2 (TRS80 PC2) and Sharp PC-1500 (Sharp PC1500) increases the memory from the standard 1850 bytes free to 26,426 bytes free.

     For the Sharp PC-1500A (Sharp PC1500A) the free memory is increased from the standard 5946 bytes to 28474 bytes free.

     Where the 1714 provides passive SRAM memory expansion, the 1744 module expands the computer SRAM and allows the entire memory (RAM and ROM) of the PC2 to be examined and the SRAM to be modified via a USB connection and windows UI: The full 24K can be uploaded in less than 10 seconds.  The USB controller also has a flash storage area allowing the entire RAM image of the PC2 to be saved in flash and then restored after a power cycle or hard reset.