Ashen's N64p ~worklog~

[Ashen]

So I finally got my USBASP programmer in the mail. I got a few atmel chips programmed today and wired one up to a regular 64 controller to test:

Pretty simple to setup, program and wire up and it works great! I haven't tested with a 3DS analog yet, but I'm confident there will be no issues. One nice feature this chip/software combo has is that you can wire it up so that if you hold the B button in when you boot the N64 it extends the range of the analog stick through the software flashed to the chip. This could be super useful for 3DS analogs.

Anyway, I've got about 8 more of these chips that I don't really need atm, so if anyone wants a pre-programmed bare chip I'll sell my remaining stock for $3 for a bare chip, and $6 for one that's got all the components already wired and ready to go. If there's enough demand, I can always order more.

I'll update again after I plop this in my portable and let everyone know how it works with the 3DS analog.

 

[βeta]

Can you post your code?

 

[Ashen]

Its not my code, but here ya go.

http://code.google.com/p/n64-joystick-translator/

EDIT: Whoops, the above is kylejw's stuff, I'm actually using Micro's program: http://www.mediafire.com/?q4232gx1w2q2w0s

 

[bud]

Is there a smaller version of that chip? The chip size is the only thing that's turning me off about this

 

[Ashen]

Yea, you can use an attiny24 microcontroller, which is about half the size of the atmega8. They're a bit more expensive though. The atmega8 chip really isn't that big, its only slightly larger length wise than the china converter boards.

 

[public-pervert]

You can also use the SOIC version of the ATTINY24, witch is about 5x9x2mm

 

[Ashen]

So I've got these atmega8 chips working pretty wonderfully with the 3DS analogs. I had to reprogram a few a couple times to get it right because I had to tweak the code a bit to get them working properly. The best part is that we don't need any odd voltage input into the 3DS stick now with this converter, your 3DS stick can work perfectly from the standard 3.3v that analog sticks normally take. The only crappy thing about this is that the chips aren't interchangeable between a normal analog and a 3DS one, as it has to be programmed for one or the other. Still, pretty cool to have perfect range from a 3DS stick without messing around with voltages and such.

Also:

viewtopic.php?f=3&t=10646

 

[public-pervert]

Could you please post the modified code? It'll be usefull for other peoples

 

[Ashen]

'© Jakob Schaefer 2010
'This source code file is for personal use only. Use at own risk.

$regfile = "m8adef.dat"

'8MHz = highest internal frequency of the ATMega8
$crystal = 8000000

'configuring the ADC, its resolution is 10bit per channel
Config Adc = Single , Prescaler = Auto , Reference = Avcc
Start Adc

'pins for the output of the X-axis
Config Portb.1 = Output
Config Portb.2 = Output

'pins for the output of the y-axis
Config Portb.3 = Output
Config Portb.4 = Output

'we want to activate the internal pullup resistors for the I/O pins we don't need to prevent them from floating free
'...many, many unused I/O pins....
Portb.5 = 1
Portc.0 = 1
Portc.3 = 1
Portc.4 = 1
Portc.5 = 1
Portd.0 = 1
Portd.1 = 1
Portd.2 = 1
Portd.3 = 1
Portd.4 = 1
Portb.6 = 1
Portb.7 = 1
Portd.5 = 1
Portd.6 = 1
Portd.7 = 1
Portb.0 = 1



'variables in which the 10bit value of the ADC will be stored
Dim X As Integer , Y As Integer

'R will affect the range of X- and Y-axis (1024 * R / 128)
'R=20 means the range of each axis will be 160 steps (1024*20/128=160)
'If you drive Pinb.5 low (Pin 19), R will be 21 resulting in a slightly higher range of 168 steps
Dim R As Byte
R = 32
If Pinb.5 = 0 Then R = 34

'init X axis. t
X = Getadc(1)
X = X * R
Shift X , Right , 7 , Signed

'init Y-axis
Y = Getadc(2)
Y = Y * R
Shift Y , Right , 7 , Signed

'variables to store the old X and Y values for comparison in the next round
Dim Oldx As Integer , Oldy As Integer
Oldx = X
Oldy = Y


Dim Xwheel As Byte , Ywheel As Byte
Xwheel = &B11001100
Ywheel = &B11001100

Dim I As Byte

'in these two variables we're storing the number of steps we have to process for each axis
Dim Xsteps As Integer , Ysteps As Integer



'main loop:
'-------------
Do

'get and store X-value; resolution = 10 bit * 10 / 64 = 160 steps / axis
X = Getadc(1)
X = X * R
Shift X , Right , 7 , Signed

'get and store X-value; resolution = 10 bit * 10 / 64 = 160 steps / axis
Y = Getadc(2)
Y = Y * R
Shift Y , Right , 7 , Signed

'calculate the number of steps we have to process
Xsteps = X
Xsteps = Xsteps - Oldx
Ysteps = Y
Ysteps = Ysteps - Oldy



'stay in while-loop until all steps of the X- and Y-axis are processed
While Xsteps <> 0 Or Ysteps <> 0

'steps of the x-axis
If Xsteps > 0 Then
Rotate Xwheel , Left , 1
Xsteps = Xsteps - 1
Elseif Xsteps < 0 Then
Rotate Xwheel , Right , 1
Xsteps = Xsteps + 1
End If

'steps of the y-axis
If Ysteps > 0 Then
Rotate Ywheel , Right , 1
Ysteps = Ysteps - 1
Elseif Ysteps < 0 Then
Rotate Ywheel , Left , 1
Ysteps = Ysteps + 1
End If

'output the new gray code to the pins for XA, XB, YA & YB
Portb.1 = Xwheel.1 'XA
Portb.2 = Xwheel.2 'XB
Portb.3 = Ywheel.1 'YA
Portb.4 = Ywheel.2 'YB


'we have to wait a little bit for processing the next steps because otherwise
'it would be too fast and the IC in the N64 controller would skip some steps
Waitus 10

Wend

'store the values of both axis for comparison in the next round
Oldx = X
Oldy = Y

Loop
End