Some questions about pin usage of 4040 and 4201

[Mizutsuki Raki]

Hello :), I have some questions about pin usage of 4040.


1.
In IMG_0130, I wrote '(?)' near RESET IN.
Someone said 100K resister is OK, but another schematic have used 470K, and 4040 manual have used 560K resister. And there's no description about the usage of this resister. What value can I use?

2.
In IMG_0131, I ignored INT ACK(8) and STOP ACK(5) pin. And I tied INT(7) and STOP(6) to +5V and added 4.7K resister. Because I don't want to use it.
https://drive.google.com/file/d/0B9rh9tVI0J5mNzY1MGE2YWMtNzkwZC00OTQ0LWIzNDMtNmI0NDI1MWU5NmQ1/view
Refer to this document, the option which I used, is 'single step'. However, this have used 10K resister. What value can I use?
Anyway, I will test every case, but I hope to someone's help.

3.
I don't want to use TEST function, so I tied TEST pin of each chip, 4004 and 4040. Is it OK? (or leave it disconnected?)


Thanks very much. Have a nice day.

[bccwchan]

I don't know the answer, but I saw you did a good work in writing a beautiful chart. (You must be the good student).

[hardwarecop]

Hello!

For the 1st, RESET IN issue:

http://bitsavers.trailing-edge.com/pdf/intel/MCS40/MCS_40_Microcomputer_Set_Advance_Specifications_Sep74.pdf

Might have a look at this document here which seems to be useful for implementing the reset circuit and some other things. There it says that

"Input to which RC network is connected to provide power-on reset timing."
and
"RESET input. A "1" level applied to this pm clears all flag and status flip-flops and forces the program counter to O. To completely clear all of the address and index registers, RESET must be applied for 96 clock cycles (12 machine cycles)."

So maybe the 1M resistor is used to "charge" that RC network or so for at least 96 clock cycles.

[Mizutsuki Raki]

Thanks for new information, and nice Mac

I have seen many values. 100K, 470K, 560K, and 1M.
Some official docs uses 560K, so I'll test clock generator with 560K first.

-----
http://www.youtube.com/watch?v=uIppMMuaWwI
This person have used 100K, but works correctly.

[hardwarecop]

Oops I didn't meant to capture my whole screen. I didn't even notice

So yeah I think they might be just indicative values where most of them in that resistance range would work like the same. The same thing might work for 2. Sometimes I also try values - and most of the time it just works

[lhf_james]

Are you trying to connect 4004 and 4040 together?? They can not appear in a single system, so don't plug them in at the same time.
1)
The resistor is for charging the capacitor, larger value means longer reset time. So increasing it will don no harm to the system. Just like hardwarecop says.
2)
I suggest to connect INT and STOP to VCC with two resistors individually
3)
TEST of each chip can be left open, or connected to Vdd or VCC. There's no need to tie the pins of 4004 and 4040 together. There's an instruction that reads the level on this pin and do jumps or something. If you don't use that instruction this pin will be no use. However you may connect a pull-up resistor and a button to this pin to have some fun

[Mizutsuki Raki]

Always thanks, lhf_james.
You are the best