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AD0-7: Me trying to grab its address first!

A project log for Let's experiment: NEC V20 + FPGA

What happens when you connect a NEC V20 to an FPGA? Let's find out!

nyh-workshopNYH-workshop 05/20/2019 at 15:080 Comments

Lucky me I have a bit of a long holiday here and I managed to have the FPGA to grab the address from the AD0-7 first. The bad news is, the FPGA couldn't grab anything on the address. Going back to the basics and to further understand how this 8088 works, I wired up the extra 74373 on top of the 74245,  with reference to http://www.homebrew8088.com/

And when I connected the first four bits on the 373's Q0-Q3, I'm getting this:

I'm suspecting that it's working alright, since the address is counting upwards (the 8088 starts at address FFFF0).

The more tough part is I do not have enough pins on the FPGA board's connector to even connect that latched address A0-A7, so I'm cooking up some method on how I could effectively make this run properly without adding even more stuff on top of it!

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