How To: Build your own Custom ROM!

[ppc6700freak]

Originally Posted by colonel

Still having trouble getting reg edits to stick. Mostly something is gettng corrupted when converting back from txt to .hv. The batch cranks out a 28kb .hv file that is much smaller than the default.hv in the dump file. When I convert it back to text it is only a few of the registry lines. Not sure what is happening. Have you seen this?

For instance, I will do something very simple like .hv to txt. Open, add REGEDIT4, save as unicode. Then just do the quick change to enable smartdialer. Save, close, txt to .hv and everything is gone. Hopefully this will ring a bell.

colonel, how did you resolve this issue?

Thanks.

[colonel]

Hang tight. When I get home I will post a screen shot showing exactly how stuff should look. Remember, you can't have word wrap on. I had to open Notepad with nothing in it, turn off word wrap, then "Open" the reg text. Add the REGEDIT4 and save as Unicode first. It should basically look like this:

REGEDIT4

[HKEY_LOCAL_MACHINE\......]
@="string value"

[HKEY_LOCAL....................]
"DLL"="whatever.dll"

Remember to pay attention to spacing and syntax. When you run the txt-to-hv utility, if it shows an error, it will list the key where the error is. I always save my default.txt and user.txt in two places since those utilities take the one you have in the HV Tools folder. So, if I have an error when converting to .hv, I erase the .hv and boot file that were created. I can then go back to my saved txt file and correct the issue, save in the HV tools folder and somewhere else and then attempt to convert back to .hv again.

[colonel]

Okay, here is the .NET CF2.0 "module". This one is pretty simple. Using the process in this thread, just paste the files into the dump folder and add the registry entries to either .hv file.

[sd_matto]

Hello-

Great work by Mike (for the tools), and by Helmi, Mike and Colonel (for the new 3.3 based ROMs).

Helmi's ROM (and the Colonel's, which has two extra copies of a 680K file, one in \windows and the other \windows\pem\) can be easily fixed via the custom tools following instructions on here. In addition, the smartdialer hack can be similarly fixed.

As I was working my way through this custom ROM exercise, I thought about UPX and system files. At first, I tried a blanket UPX of EVERYTHING; did not go over well. So, I was wondering about people's experience with UPXing ROM files, and, specifically, what ROM files can be safely UPXd. Your thoughts?

Thanks in advance.

[schettj]

The rom itself is compressed (apparently) so UPXing on top of that might not always be a win - according to the long long long rom kitchen thread at least.

The only reason to UPX stuff in rom is to make enough space to fit more stuff into rom. At least in the Rom Kitchen you can see when you go over the limit, and if you do you need to pull out something to get back under the limit.

[colonel]

Exactly schettj, that is the way I understand it as well. Many people believe that removing programs from the rom will give them ample amounts of Storage and Program memory. The fact is, though, that its just not true (that I have seen anyway). My .nba files are always 63.2 MB regardless of what I put in them. Actually, my dump folder is 94MB right now so that shows the compression that is taking place.

[luv2chill]

I haven't gotten much into the UPX thing yet (it's on my list!) but I believe one of the side effects of UPX compression is quicker load times (because the speed bottleneck is in reading the file from flash rom). So since a UPX'ed file is smaller in size, it can be copied from the flash rom to memory faster and will therefore speed up its load time.

So even if it doesn't directly give you more storage memory it may still be worth trying to UPX some stuff if it means that stuff loads faster. Also, as you've said it allows you to pre-install more stuff in the ROM so that you don't have to use your storage memory for it.

Only problem is that it seems that UPX'ing the wrong files can cause all kinds of gremlins, so there's a ton of trial and error involved. A wiki page with summaries of which files can be successfully UPX'ed and which ones can't would be a good way to go (maybe one already exists somewhere?).

[kwyatt]

how would i go about upxing some system files using either this or the rom kitchen method, also what system files are ok to upx?

[crencom]

I cannot get past a certain point with this process. I can dump the .nba file. I edit what I want on the dump folder. Then when I run the process to restore the edited Dump folder to a .nba, it doesn't seem to build the .nba file. I assume the new .nba would appear in Folder 2, but it is.nt there, just the original .nba. Anyone have any ideas.

scott

[colonel]

That is your .nba. The app just patches it with your new stuff. Just copy it to folder 1 and encode.