Unraveling the NEC V-series labeling

[anheier]

NEC has an interesting, yet confusing processor identification scheme. The V30 is identified as a 8086. The V20 is an 8088. The V40 is an 80186. What about a V25, V35, V45, V50, and V55? Where do these fit?

Norm

[gshv]

V20 is an 8088 + additional (similar to 80186) instructions + 8080 instruction set.

V25 is a microcontroller version of V20, i.e. V20 + on-chip ROM + on-chip RAM + on-chip peripherals.

V30 is an 8086 + additional (similar to 80186) instructions + 8080 instruction set.

V35 - I don't have datasheet on it, but suspect it's V30 + on-chip ROM + on-chip RAM + on-chip peripherals.

V40 is a V20 + many on-chip peripherals

V50 is a V30 + many on-chip peripherals

I don't have datasheets on V45 and V55.

So, if you look at the instruction set of V20/V30 then you'll see they are closer to 80188/80186 than to 8088/8086. They also a bit faster than 8088/8086.

This reminds me - I need to create separate pages for V20/V30/... processors, I don't think listing them together with other 808x processors is a good idea.

Gennadiy

[anheier]

Thanks Gennadiy,

That's what I was getting at. What catagory do these belong in, the 8086, 8088, or the 80186 family . I like your idea of a separate catagory.

Norm

[gshv]

Putting the chips into single "NEC V-series" category IMHO is better than listing them together with 808x processors. Even better - if you have many Vxx chips then you can create separate category for each type - "V20", "V25", "V30", etc. I don't have many Vxx chips now but I will probably go this route (with multiple categories).

Gennadiy