3 ms·

I feel like there was a lot of heavy bias toward the substrate in this write-up. I was hoping for more detail on the sequence of events, as operations cascade t

I feel like there was a lot of heavy bias toward the substrate in this write-up. I was hoping for more detail on the sequence of events, as operations cascade through the transistor architecture, to resolve input values to a result. For example, if arithmetic operations are fairly objective, why is microcode needed in between the processor logic and the user-facing pinouts? Or is the microcode not adjustable firmware, but rather a fixed set of routing options to engage components appropriately for a given operation?

kens 8y ago
Yes, this article was 100% focused on the substrate bias generator, since I wanted to start with a self-contained piece. I realize it's a bit of a strange focus, but hopefully it was interesting. As far as the microcode, I'm not sure I understand your question. The microcode is fixed firmware, stepping the 8087 through the procedure for complex operations such as logarithm. Essentially, the microcode has mini-programs that the 8087 runs to perform its functions. I'm still researching how the microcode is actually implemented.