Have 25 74HC595 devices, I originally thought, by not paying attention that they were IO extenders but they are in fact just OUTPUT extenders, will still be able to use them for something, have an idea for something to do with LED’s. As they are chainable I could have a lot of LED’s controlled from them, with 25 x 8 LED’s possible, would need some real power management though, lol.
I have now ordered some MCP23017 chips which give 16bit IO, using I2C, which will do what I wanted to do originally, also can chain up to 8 of them addressable. Though I only ordered 5, which should be enough for me for now.
Will punish myself later with a stick.