HD loader example

12 October 2012, 15:56

Hi,

I've already posted similar topic on Flashtro forums but it looks like I should've start here.

I've been trying to fix some NDOS game to load from HD. I don't want to use WHDL, since it's too
much for my A600, also it's better way to get into coding.

I've already located track loader,
dumped all the files, found neccessary offsets to patch, etc. Then I got stuck. Could anyone tell
me if there's any tutorial/example how to load files from HD? I googled a bit but could't find
anything specific.

redblade · 12 October 2012, 16:14

I think dos.library isn't to friendly under _LVOForbid? Isn't that why Syndicate sometimes crashes the HD and you have to wait a while for it to revalidate itself on reboot?

StingRay · 12 October 2012, 16:28

This is not too trivial. At the start of your patch you need to save the "zero page" (first 1k should be enough) since important system data is stored there. Then, when you need to load from HD, you have to restore the "zero page" (it's not exactly zero page but I called it like this ever since my 64 days) and re-enable ports/timers interrupt so you can actually use dos.library for loading. If you get stuck I might attach the source for one of my old HD patches from back in the day (1996/1997).

15 October 2012, 15:52

Ok, thanks, I'll check if it works that way!

StingRay · 16 October 2012, 21:56

If you do it right it'll definitely work that way.

12 October 2012, 15:56	#1
st! Posts: n/a	HD loader example Hi, I've already posted similar topic on Flashtro forums but it looks like I should've start here. I've been trying to fix some NDOS game to load from HD. I don't want to use WHDL, since it's too much for my A600, also it's better way to get into coding. I've already located track loader, dumped all the files, found neccessary offsets to patch, etc. Then I got stuck. Could anyone tell me if there's any tutorial/example how to load files from HD? I googled a bit but could't find anything specific.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Hardware File Loader	h0ffman	Coders. General	9	02 December 2010 16:40
WinUAE Loader + WHDLoad problem	BobbyBobBob	support.WinUAE	5	07 January 2010 22:35
HELP........with getting winuae loader to work.	mrbailey1890	support.WinUAE	3	08 July 2009 23:47
RNC IDE CD32 loader	Galahad/FLT	support.WinUAE	19	24 June 2006 10:05
IFF Loader v1.0.0 is released... :)	Steve	News	11	17 September 2004 19:10

12 October 2012, 16:14	#2
redblade Zone Friend Join Date: Mar 2004 Location: Middle Earth Age: 40 Posts: 2,130	I think dos.library isn't to friendly under _LVOForbid? Isn't that why Syndicate sometimes crashes the HD and you have to wait a while for it to revalidate itself on reboot?

12 October 2012, 16:28	#3
StingRay move.l #$c0ff33,throat Join Date: Dec 2005 Location: Berlin/Joymoney Posts: 6,865	This is not too trivial. At the start of your patch you need to save the "zero page" (first 1k should be enough) since important system data is stored there. Then, when you need to load from HD, you have to restore the "zero page" (it's not exactly zero page but I called it like this ever since my 64 days) and re-enable ports/timers interrupt so you can actually use dos.library for loading. If you get stuck I might attach the source for one of my old HD patches from back in the day (1996/1997).

15 October 2012, 15:52	#4
st! Posts: n/a	Ok, thanks, I'll check if it works that way!

16 October 2012, 21:56	#5
StingRay move.l #$c0ff33,throat Join Date: Dec 2005 Location: Berlin/Joymoney Posts: 6,865	If you do it right it'll definitely work that way.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)