N64 Portable Help!

taiku · Post by **taiku** » Tue Dec 30, 2008 2:39 pm

I have the PDV 0700 battery giving at least 8 volts. When I do not connect the n64 the screen turns on and runs off the battery fine. But when I connect the 12+ and (3) negative terminals of the N64, the screen wont turn on. (3+ is not connected nor is the Ti chip wired to this in any way).

Did I fry my n64?
What can I do to troubleshoot this?
What should my next step be?

deviouskoopa · Post by **deviouskoopa** » Tue Dec 30, 2008 2:49 pm

For future reference, you cannot power something that requires greater than 8V (12V in your case) from an 8V battery. For an N64p, you need a voltage regulator to step the voltage down to 3.3V. The screen still requires 8V though.

Look at this diagram... (I dunno how you haven't seen this yet)
http://forums.benheck.com/viewtopic.php?t=14556

taiku · Post by **taiku** » Tue Dec 30, 2008 2:54 pm

Thats how I wired it but wired like that nothing turns on. When all pieces of the n64 are disconnected the screen turns on.

Mario · Post by **Mario** » Tue Dec 30, 2008 3:19 pm

So when yo uconnect the N64s 12v line, the screen turns off? Your battery can't handle the amp draw.

deviouskoopa wrote:For future reference, you cannot power something that requires greater than 8V (12V in your case) from an 8V battery. For an N64p, you need a voltage regulator to step the voltage down to 3.3V. The screen still requires 8V though.

The 12v to the N64 goes to a 7805, so the 12v line can powered with as low as 7.5v.

taiku · Post by **taiku** » Tue Dec 30, 2008 5:08 pm

Even using the psone screen power adapter i get the same issue.

taiku · Post by **taiku** » Tue Dec 30, 2008 5:17 pm

[*fixed] The pth08080 is giving out 5v how do i step it down more?

* Just added another resistor.

deviouskoopa · Post by **deviouskoopa** » Tue Dec 30, 2008 5:38 pm

Mario wrote:So when yo uconnect the N64s 12v line, the screen turns off? Your battery can't handle the amp draw.

deviouskoopa wrote:For future reference, you cannot power something that requires greater than 8V (12V in your case) from an 8V battery. For an N64p, you need a voltage regulator to step the voltage down to 3.3V. The screen still requires 8V though.
The 12v to the N64 goes to a 7805, so the 12v line can powered with as low as 7.5v.

Oh, where is that on the diagram? Or is it not on there.

Mario · Post by **Mario** » Tue Dec 30, 2008 6:48 pm

deviouskoopa wrote:
Mario wrote:So when yo uconnect the N64s 12v line, the screen turns off? Your battery can't handle the amp draw.

deviouskoopa wrote:For future reference, you cannot power something that requires greater than 8V (12V in your case) from an 8V battery. For an N64p, you need a voltage regulator to step the voltage down to 3.3V. The screen still requires 8V though.
The 12v to the N64 goes to a 7805, so the 12v line can powered with as low as 7.5v.
Oh, where is that on the diagram? Or is it not on there.

The PSone screen requires 7.5 to 8v, so there's no need to say anything about the 7805, because it'll run from 7.5-35v.

taiku · Post by **taiku** » Tue Dec 30, 2008 7:40 pm

So what do i do? Whenever i connect the N64 nothing turns on? I know i am getting 7.8 v from the power supply and 3.2 v from the PTH08080, but when i connect them all (like the diagram) i get nothing.

Mario · Post by **Mario** » Tue Dec 30, 2008 7:51 pm

taiku wrote:Even using the psone screen power adapter i get the same issue.

Those only give about 2.5 amps. The N64 takes 2A on the 3.3v line and 700ma on the 12v line, and an LED modded psone screen takes 500ma, so if you LED modded the screen, the total draw is about 3.4 amps, if you don't LED mod it it's around 3.9. Try using the original power adapter for the N64 and the PSone adapter for the screen, then see if it works.

Also, are the screen's and N64's grounds tied together?

vskid · Post by **vskid** » Tue Dec 30, 2008 8:09 pm

Mario wrote:The N64 takes 2A on the 3.3v line and 700ma on the 12v line, and an LED modded psone screen takes 500ma, so if you LED modded the screen, the total draw is about 3.4 amps, if you don't LED mod it it's around 3.9.

Flaw, 2A@ 3.3v isn't the same as 2A@ 7.5v. 2A*3.3v=6.6w, 6.6w=7.5v*xA. So the 3.3v line is only drawing 0.88A from the 7.5v line.
He's right other than that, you could be drawing more power than the adapter can provide.

Mario · Post by **Mario** » Tue Dec 30, 2008 8:15 pm

vskid wrote:
Mario wrote:The N64 takes 2A on the 3.3v line and 700ma on the 12v line, and an LED modded psone screen takes 500ma, so if you LED modded the screen, the total draw is about 3.4 amps, if you don't LED mod it it's around 3.9.
Flaw, 2A@ 3.3v isn't the same as 2A@ 7.5v. 2A*3.3v=6.6w, 6.6w=7.5v*xA. So the 3.3v line is only drawing 0.88A from the 7.5v line.
He's right other than that, you could be drawing more power than the adapter can provide.

Wait, what? Of course it isn't. I said the 3.3 volt line on the N64 draws 2A, and the 12 volt line draws 700mA. The 3.3v line doesn't take anything from the 7.5v line.

vskid · Post by **vskid** » Tue Dec 30, 2008 8:44 pm

Mario wrote:
vskid wrote:
Mario wrote:The N64 takes 2A on the 3.3v line and 700ma on the 12v line, and an LED modded psone screen takes 500ma, so if you LED modded the screen, the total draw is about 3.4 amps, if you don't LED mod it it's around 3.9.
Flaw, 2A@ 3.3v isn't the same as 2A@ 7.5v. 2A*3.3v=6.6w, 6.6w=7.5v*xA. So the 3.3v line is only drawing 0.88A from the 7.5v line.
He's right other than that, you could be drawing more power than the adapter can provide.
Wait, what? Of course it isn't. I said the 3.3 volt line on the N64 draws 2A, and the 12 volt line draws 700mA. The 3.3v line doesn't take anything from the 7.5v line.

PSone adapter outputs 7.5v, thus the Ti regulator uses power from the 7.5v line and the 12v is turned into a 7.5v line. Amps change with voltage. If you have a wallwart outputting 1A @ 12v, then the wallwart is drawing .1A @ 120v from the wall (excluding efficiency losses). So 2A @ 3.3v draws less amps from the 7.5v line.

taiku · Post by **taiku** » Tue Dec 30, 2008 10:52 pm

So can i just wire the 7+ of the n64 power supply to the pin on the N64?
Do i need to do anything with the ground of the N64 power supple?

bacteria · Post by **bacteria** » Wed Dec 31, 2008 3:47 am

8v is fine to power the PSone screen, the 12v line to the N64 and you must have the 3.3v connected too (via the TI card you mention) or of course nothing will happen. You can't use the 7805 from the PSone screen mobo for this, not enough amperage. You must also use decent wiring for the power; 3amp wire is a good idea.