Here is the page I was looking at. It is the 6800. https://www.jameco.com/Jameco/Products/ProdDS/43481.pdf

I am comparing the instruction execution speed of different 8 bit microprocessors. One document gave the amount of t states and machine cycles. Another one gave out values under the label of cycles. Does cycles refer to machine cycles or instruction cycles?

I read that adc takes two cycles. So the 6502 must load the alu b register, load the alu output register with the sum, and output the sum into the accumulator all in one cycle? I don't see how this is possible with the registers being rising edge triggered. How is all this accomplished on such a ...

I just took a look at every 6502 instruction and noticed non of them used the brk flag, not even the branch and set flag instructions. Does the brk flag do anything at all?

How does it take one less cycle? Does the alu increment the control matrix counter to skip a cycle?

I have one more question. In instructions like LDA 0200, FF how does the 6502 take one less cycle when the addition is not over one page. Can someone explain in the cycles of that instruction?

I am currently designing my own implentation of the 6502. All I have left to design is the control matrix. I am confused how instructions like INX take only two cycles. Shouldn't the cycles be like this: cycle 1-Load alu input register a with value of x register. Cycle 2-increment a input register ...

How does the 6502 execute the branching instructions? I looked at the schematic, but couldn't find anything.

How does the 6502 increment and decrement the X and Y registers? I orginally thought that the registers were loaded into the alu A input register and the carry was set to one, but I am not so sure anymore after I heard that the 6502 had a increment/decrement circuit seperate of the alu. Is the alu ...

I just read that the brk instruction loads the PC with the address at FFFF and FFFE. How would this work when the NMI and RESET are located at different addresses?

Thanks! Your answer was very helpful. I am planning on eventually building the hardware from ics.

I am currently in the process of designing a microprocessor. The only thing I cannot figure out is how to implement interrupts. Can anyone give me a schematic or a very detailed description on how I can add interrupts to my microprocessor? I want it to be based of the 6502.