New Project: Logic Tool

Since my plan to make a wireless breadboard did not work out, I decided to use the MCP23S17 shift registers I bought for it to make something similar. It is similar to a logic analyzer but shows information in real time rather than recording a short period of time at high resolution. It has female headers for 64 pins but so far I have only soldered 32 of them in. As time gets closer to Makevention, I'm trying to save time however I can to get my last few projects working.

With 64 pins I will have enough to monitor all of the lines of my 6502 project. Unlike a logic analyzer, I can

also switch any of the pins to be outputs. Now I am doing this with a simple GUI I made that shows or controls the lines with virtual LEDs. This saves me from hanging loads of LEDs on all the lines of my project. Later I would like to add other forms of input and output that I can drag and drop to the dark gray area in the middle of the form. This could include buttons, sliders or hex readouts like I had for my 6502 Virtual Project. At the moment, only the LEDs work and I am using them to drive the address and data lines of the 6502 socket for my graphing calculator project. This lets me check the control signals of the CPLD fairly quickly.

In the end I think this project will work out better than the plan I had for the Wireless Breadboard. When I tried the breadboard I was going to use with another project, it showed a big voltage drop across the rails. I did not know this could happen and it would have been unfortunate to build the whole project and then find out the board was not very good.