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Mcs-40

Calling the 4004 or 4040 a "microcomputer' would be a bit of a stretch. 8K ROM addressing for instructions, 4 bit words, sub-microsecond clock speed. Today, we'd probably call it a microcontroller. It's PMOS and has special support chips. The 8008 was really Intel's first general-purpose microprocessor.
 
I believe fluke used the 4040 for a keypad or display
driver. I'd guess that is what this board was for.
Even though the data was 4 bits, the instructions were 8 bit.
It could do 16K because one had individual control of the
select bits ( 2 of them ) as I recall.
With a decode you had 4 selects.
Dwight
 
2 banks of 4KB according to the 4040 datasheet You do have 2 ROM bank select signals, but they're decoded internally so that one or the other is active (cf. DB0 and DB1 instructions). Extra set of 8 registers selectable by instruction. RAM access is accomplished by I/O instructions.

Tidbit: the 4004 (same family as the 4040, but with lower capabilities) was designed as a calculator chip for Nippon Calculating Machines Busicom 141-PF calculator.
 
Chuck(G) said:
2 banks of 4KB according to the 4040 datasheet You do have 2 ROM bank select signals, but they're decoded internally so that one or the other is active (cf. DB0 and DB1 instructions). Extra set of 8 registers selectable by instruction. RAM access is accomplished by I/O instructions.

Tidbit: the 4004 (same family as the 4040, but with lower capabilities) was designed as a calculator chip for Nippon Calculating Machines Busicom 141-PF calculator.
Click to expand...

Yep, your right Chuck. Don't know what I was think. I recall some type of banking method but that obviously
wasn't it.
I did make an ICE for the 4040 while at Intel to verify 4001s and 4002s in their UPP product. There was
only one made and we used it for production testing. A long time ago so expect some brain fade.
Dwight
 
Hi Dwight--yes, it was a long time ago, but pretty heady times between about 1969 and 1973, huh? Things seemed to really rocket along. I remember when Computerworld (IIRC) opined that it was only going to be a short time between a 4 bit ALU IC and a working microprocessor on a chip. I didn't believe it, but if you think about it, there was an amazing amount of development in just a few years. I was still using mainframes built with discretes when the 8080 came out.

I know it's just an illusion, but technology in terms of breakthroughs doesn't seem to move along as quickly today.
 
Chuck(G) said:
---snip---
I know it's just an illusion, but technology in terms of breakthroughs doesn't seem to move along as quickly today.
Click to expand...

Most are limited by the power density of the 4-5 GHz clocking. Now it is just how many processors can you
fit on a piece of silicon.
It was magic back then and when they began to beat heavy iron processors with single chip
processors, life changed.
Just the realizing that one could put a relatively complete circuit on a chip was the spark.
It will take some time for the next spark.
Dwight
 
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