Results

The emulator successfully ran several test programs that we wrote. Due to time constraints we did not get a chance to test every instruction, but most of the ones that we did test worked. Although the emulator takes longer to execute instructions than a normal CPU would, we were not concerned with synchronicity for this project (if video were to be added, then it would be necessary to have the instructions be cycle-accurate, albeit scaled by a constant factor).

Our test and subsequent usage of the external SRAM chip was successful. Due to a lack of decent documentation, we had spent more time than anticipated trying to figure out how the chip operated. We also successfully configured our Xmodem protocol receiver, which read in the binary data for the programs.

The project is safe as long as nobody touches the memory chip or board while it is turned on :-) It is usable through any interface which can communicate over a serial port and can send binary data using the Xmodem protocol. We chose Hyperterm, which seemed to work fairly well.