Topic: Do I Need To Cut A19 Trace For Multi Bios On V1.0? (Read 50 times)

racer135 · « **on:** February 09, 2004, 04:00:00 PM »

I was reading the dudes tutorial on a multi bios TSOP. I actually did the modification to my V1.0. On the tutorial it says to connect A19 (MSB input to TSOP) to a SPST switch and then connect the remaining two ends of the switch to VCC (5V) and to Ground. It does not says anything about cutting the A19 trace before the point where the switch is intalled. My concern is that this point (A19) should be connected to an output of someting on the board. Wouldn't that cause a short circuit if we force Vcc or Gnd to A19 without cutting the trace? For instance the circuits tries to read the lower part of TSOP (where A19 is low) and A19 is tied to Vcc without any resistors in the path. Am I missing something? I am not sure if I should open again and cut that trace. <

Dreamcazman · « **Reply #1 on:** February 09, 2004, 08:22:00 PM »

If you want to totally fuck your Xbox, go ahead and cut the trace. The 5v, just stops the Xbox seeing the first half of your TSOP, grounding it only lets it see the second half (I think I got that right)

If you want to just have 2 bios', follow the tutorial exactly. If you want to have 4 bios', install a switch on A18 as well. <

Lubs · « **Reply #2 on:** February 10, 2004, 05:28:00 AM »

I did this on Saturday and followed the tutorial. I used an SPDT switch however, not sure if that makes a difference.

I connected A19 to the middle. VCC 3.3 to one side, and after trying ground to the other side and having it come off a bunch of times I just put it to the chassis. Works beautifully... many thanks to the knowledgeable folks around these parts.

<

racer135 · « **Reply #3 on:** February 10, 2004, 05:59:00 AM »

So some people have used this mode for a while? Cutting the trace should not damage your XBOX (you are using a switch to select the upper or lower part of memory in both cases. It will just avoid connecting an open collector logic pin forced to Vcc or Ground. Doing that could break the transistor in the MCPX that switches the address line. Are you guys following? <

Exobex · « **Reply #4 on:** February 10, 2004, 07:38:00 AM »

dmk11 · « **Reply #5 on:** February 12, 2004, 11:06:00 AM »

lordvader129 · « **Reply #6 on:** February 12, 2004, 11:19:00 AM »

you could also use a center-off switch, then after booting put it back to center so the current is no longer flowing anywhere <

Scan-C · « **Reply #7 on:** February 12, 2004, 11:23:00 AM »

teh mcpx jsut runs a little hotter than normal. 2-3°C. put a heatsink on it and it will last longer than one in a unmodded box. may v1.0 has the tsop flashed and working this way since feb 2003

This post has been edited by Scan-C: Feb 12 2004, 07:24 PM <

racer135 · « **Reply #8 on:** February 13, 2004, 02:11:00 PM »

I decided to open the XBOX again and cut the trace. And reinstall everything back. I also flashed with Evox M7 and installed the 3935 Dashboard. Now I have a dual boot setup. It is working great. I already made my first backup. This is cool. <

Author Topic: Do I Need To Cut A19 Trace For Multi Bios On V1.0? (Read 50 times)