Is tri-boot possible REBIRTH ... question on schematics inside

[exrazhell]

I repost my old post from xboxhacking - general here as it's a better place to have help ...

I want to make a tri-boot using an SST39SF040 chip, soldering it above the original SST39SF020 chip with her original firmware.

However, looking at differents schemes presents in the forum I'd like to be sure that I'm not doing a supid operation.

I choose an SST39SF040 (70-4C-NH) to make the "tri-boot" I was speaking of. So I want to choose between the original chip and the SST39SF040 one AND between bank 0 & 1 of this SST39SF040 chip.

But schematics showing us how to solder a second chip on the original one (I used the following picture) show that we have to solder pins A18 & VDD together.




However the tutorial "TightMod360 by LittleJonny tells us to join pins A18 or VDD (or both) to pin CEx on the lower original SST.

AND if I want to choose between bank 0 and 1 of the ST39SF040 I have to leave A18 and VDD WITHOUT permanent contact (the switch decides what bank will be used)

The first question is : do I have to solder just pin A18 or VDD to make the tri-boot possible ?!?!?! I'll solder pin A18 with the other A 18 from the original chip, then to a couple of resistor and finally to each CEx of each chip (SSTSF020 and SSTSF040) : is it right

The second question is relative to the tuto of the pic used ( http://www.chipper.se/forums/index.php?showtopic=5011 ) : it tells us to cut a track on the DVD mobo :



I never heard to cut that track on xbox hacker BBS >>> what's this manipulation so

Third question : on the schematic shown before it's shown that pins A18 & VDD are connected together and with the original chip ; it's just a resistor that makes the link between this differents pins and the two CEx (who are connected together thrrough two 10kohms resistor on the schematic => is it all ok ) => is this schematic right for the tri-boot i want to do



Is this final schematic is right for what I want to do



(in this scheme I placed green and orange LED before the switch as I found in a previous scheme => does it take power from the chip or will I have to lace LED after the switch using power from the PCB of the DVD Drive )

Thanx for the future answers .... and for an eventual schematic to show me the way to do (^_^);

Sincerely

eXraZ

[exrazhell]

Can`t edit my post ...

I found answers for all my questions here : https://www.console.se/download/xbox360dualboot.pdf  the track on the TSOP version of the chip is cut to prevent permanent connection from the original chip CEx pin  ...

I can solder together pins VDD only (or A18) from the two chips to a couple of k resistor then each extremity of resistor to each CEx from the two chips then to the switch.

Problem with internal dual boot with SST39SF040 won`t exist at all then ....

Just confirm my final schematic is ok please !!!

Best regards,

eXraZ

[exrazhell]

Can't edit/modify my post   ....   

Could someone confirm if my last schematic is right to make tri-boot using a SST39SF040 as a second chip with 2 banks/firmwares in it (selection of one or the other firmware with a switch) soldered above the original SST39SF020 chip (selection of one or the other chip with an other switch) 

Thanx for answering ...

Best regards,

eXraZ

[creatox]

Hello,

Can't give you any answer, sorry. But it's very interesting.

I got a question also.

The SST chip, must it be a SST39SF020A (see pdf manual) or could it be another type? There a lots of different chips and I got some aladdin chips with this type: 49LF020. Is this chip compatible?

[exrazhell]

I don't think that SST49LF020 could be used because of the way that the chip works (I'm too noob to explain how but if think I'm right on this point  ) : it's just a certain type of chip that could be used as it works in a certain way ...

I read lot of posts on this (and others) forum and one tells about substituing the original SST39SF020 chip by a SST39SF040 one : the only difference between this two chips are the lenght of the memory contained inside the chip : 256Ko for the 020'version and 512Ko for the 040'version (I saw chips with more than 512Ko but what could be the interest >>> there are only three firmwares which could be used for one type of DVD-drive : the original firmware, the firmware to play backup, and the firmware to make backup through the PC).

However there are differents versions inside one model : for example I choose an SST39SF040 (70-4C-NH) >>> the numbers and letters between "(" & ")" are caracteristics of the chip >>> just search for "dual firmware epoxy removal video" tutorial in the Research & Technical XboxHacking\Hardware TECHNICAL section
 
Thus, I'm always waiting for someone who can confirm me that my final schematic is right  (chip still at home, just waiting for the VIA6421L PCI SATA card to begin the hack ...)

Thanx for answers ....

eXraZ

[exrazhell]

A new schematic more CLEAR ...

[Heet]

Buy the samsung drive for pc that kreon made a hacked firmware for.  Then use that german dudes tool.







Like a big slice of cake that way.  Cant wait to work with the SS after Kreon posts his update.