6502 as a Service

Summary

auto light dark 6502 Available in the Chiplab Run your programs against a real 6502. 6502 As A Service. The 6502 is now available in the Chiplab! This allows you to upload your programs to be queued for running against a real 6502 chip. For each cycle of execution, you can observe the values of all the busses of the physical chip. This can be used in place of an emulator for a highly accurate way to test your 6502 programs. It can also be used to research the behavior of this chip, which I believe will be an effective way of developing highly accurate emulators. Towards the end of the article I’ll share a repo in case you’d like to help. You can run your programs against a real 6502 chip today. The rest of this post will cover some technical details involved in getting the chip online. Using the 6502 Chiplab. The system is designed to allow you to write code in assembly language, or upload your pre-assembled programs. These will be queued for execution on the chip. After it is your turn, your program will be allowed to run for 100 cycles, which takes around 1 second. Once your program is finished running, you will be provided with a trace. This shows the values of the address(16 bits) and data(8 bits) busses. Your programs can write to memory if you want to see some result captured in the trace. How does it work? The 6502 interacts with all peripherals though the memory bus. The 6502 has some internal state that cannot be viewed directly, but otherwise can be throught of as reading and writing from memory repeatedly. The system, included the 6502 and other peripherals like memory, is synchronized through a signal called the clock. When the clock signal changes, all connected peripherals take this as a signal that they can do one extra step of work. At each change of the clock, the chiplab monitors the address bus, and updates the data bus to provide the value corresponding with your program at that address. In this way the lab simulates the surrounding environment f...