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PostPosted: Fri Aug 31, 2012 3:34 pm 
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And if I just omit the capacitor to, how do the first schematic will look like ?

(I hope I'm not bothering you, but I'm a really dummie in electronic stuff.....)

It seems that the second schematic would be must easier for me......but do you think that it has good chances to work ?


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PostPosted: Fri Aug 31, 2012 7:19 pm 
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You're not a dummie :p

To reassure you, I've gone and tested the most recent one I posted on mine: it works just fine.

(Reposting: )
Attachment:
cicremove.png
cicremove.png [ 3.96 KiB | Viewed 3581 times ]


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PostPosted: Fri Aug 31, 2012 10:55 pm 
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hey again.. the 1hz pulse i was referring to is called a reset "signal" or "pulse".. every time you hit the reset button it clocks the CIC in the cart.. or anything else connected to that line.. the circuit you're building is called a "power on reset" or "POR" you can look it up :D

so my statement on lifting pin 4 of the inverter still stands lol
i can see reusing the capacitor but you should have a 10k resistor.. it's a logic circuit :roll:

you can stop trying to bash me.. its going to be alright :lol:
i'm still not getting reply's to this thread FYI just checking in

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PostPosted: Fri Aug 31, 2012 11:52 pm 
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You still have not explained why anything cares that CIC CLOCK isn't a 4MHz square wave. It's also not a 1Hz square wave, a 1 Hz pulse train, or a 1 second one-shot. You could call it a 10-100ms one-shot.

However, there are at least two reasons that it doesn't matter whether or how we clock the CIC on the cartridge—first, the CICs are dynamic logic, so if it's clocked slower than 10kHz or so it'll just crash anyway, and secondly, unlike in the SNES where some games lock the ROM if the stream to the CIC KEY isn't valid, nothing in the NES does so here it doesn't matter. As a result, there's no need to disconnect CIC CLOCK by lifting pin 4.

The only things connected to the input there are: a 0.1µF capacitor to 5V, a 0.01µF capacitor to ground, the switch to 5V, and the resistor to ground.
The 74HCU04 has a maximum input leakage current at 25°C of 0.1µA, and 1µA over the full temperature range, which is still smaller than the current through the 1MΩ resistor over the entire relevant voltage range (It could be comparable once the capacitor has charged the the node to below 1 volt, but at that point the output is firmly into TTL logic high output). Thus there is no reason that the resistor needs to be "at most 10kΩ" since this is just a passive timing circuit.


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PostPosted: Sat Sep 01, 2012 1:24 am 
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lidnariq wrote:
You're not a dummie :p

To reassure you, I've gone and tested the most recent one I posted on mine: it works just fine.

(Reposting: )
Attachment:
cicremove.png


Thank you for have testing it, for sure it's reassure me.

So I just need to desolder only one pin of the 1M resistor, and resolder it to the C6 point ?


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PostPosted: Sat Sep 01, 2012 4:12 pm 
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lidnariq wrote:
You still have not explained why anything cares that CIC CLOCK isn't a 4MHz square wave. It's also not a 1Hz square wave, a 1 Hz pulse train, or a 1 second one-shot. You could call it a 10-100ms one-shot.

However, there are at least two reasons that it doesn't matter whether or how we clock the CIC on the cartridge—first, the CICs are dynamic logic, so if it's clocked slower than 10kHz or so it'll just crash anyway, and secondly, unlike in the SNES where some games lock the ROM if the stream to the CIC KEY isn't valid, nothing in the NES does so here it doesn't matter. As a result, there's no need to disconnect CIC CLOCK by lifting pin 4.

The only things connected to the input there are: a 0.1µF capacitor to 5V, a 0.01µF capacitor to ground, the switch to 5V, and the resistor to ground.
The 74HCU04 has a maximum input leakage current at 25°C of 0.1µA, and 1µA over the full temperature range, which is still smaller than the current through the 1MΩ resistor over the entire relevant voltage range (It could be comparable once the capacitor has charged the the node to below 1 volt, but at that point the output is firmly into TTL logic high output). Thus there is no reason that the resistor needs to be "at most 10kΩ" since this is just a passive timing circuit.


you don't need to tell me how the CIC works :lol: I have a few on a bread board on my desk hooked up to my computer and AVR in front of me.. the clock divider wouldn't care how slow the pulse is it's still going to count.. the clock in is basically a flip-flop... the slowest they can run that i've tested with was around was around 300hz (on a bread board) if i remember correctly.. it wouldn't crash unless you hit the reset button at that speed.. anyway I'm just going to leave it at you know you're right because my AVR project is do for release this week and i don't want to waste any of my free time on anything unrelated..

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PostPosted: Sat Sep 01, 2012 4:39 pm 
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satchsatch33 wrote:
So I just need to desolder only one pin of the 1M resistor, and resolder it to the C6 point ?
Yes, specifically the outside hole (which is ground). However, I don't know if that's easiest. Regardless, don't forget the other two wires.


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PostPosted: Mon Sep 03, 2012 1:20 pm 
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Hi Lidnariq,

I have showed your schematic to the electronic seller, and he told me that he could'nt understand, reading at your schematic, the way to desolder and resolder the 1M resistor....(Regarding 1M resistor, do I need to desolder the R1 or the 1M point ?)


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PostPosted: Mon Sep 03, 2012 10:30 pm 
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Here's a photograph of it on my board.


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cicremove2.jpg
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PostPosted: Tue Sep 04, 2012 2:39 pm 
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here's a picture of what the my circuit looks like
Image

also started a thread about why the pin 4 mod doesn't work

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PostPosted: Tue Sep 04, 2012 5:07 pm 
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Why'd you kill the 7404's pin 4? Wrong pin 4 if that was for the lockout mod...


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PostPosted: Tue Sep 04, 2012 5:41 pm 
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:lol: no it's the output of the inverter that goes to the games CIC clock line
i posted a schematic earlier in the thread.. i'm sure someones done that though :)

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PostPosted: Tue Sep 04, 2012 6:50 pm 
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3gengames wrote:
Why'd you kill the 7404's pin 4? Wrong pin 4 if that was for the lockout mod...
He felt he needed to keep CIC CLOCK OUT (to cartridge and expansion port) floating instead of driven. I'm not clear whether I have persuaded him that's not true, or whether he actually has a reason to do that.


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PostPosted: Tue Sep 04, 2012 7:21 pm 
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lidnariq wrote:
3gengames wrote:
Why'd you kill the 7404's pin 4? Wrong pin 4 if that was for the lockout mod...
He felt he needed to keep CIC CLOCK OUT (to cartridge and expansion port) floating instead of driven. I'm not clear whether I have persuaded him that's not true, or whether he actually has a reason to do that.


it's just personal preference.. i don't think the reset pulse would damage the jcic.. or retro zones ciclone..

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PostPosted: Sat Sep 08, 2012 8:04 am 
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lidnariq wrote:
You're not a dummie :p

To reassure you, I've gone and tested the most recent one I posted on mine: it works just fine.

(Reposting: )
Attachment:
cicremove.png




Hey, im reading this a while and i have an NES who dont want to work with Pin 4 CIC mod, so i built this easy circuit.

Works now with Pal B (standart here) and Pal A, only the SMB+World Soccer + Tetris dont go back to title screen with the reset button.

Thanks


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