So I have finally been able to get my A1200 working with AmigaOS 4.1 FE

I have been having issues getting RuninUAE working, which I understand will be too slow due to the PPC being a 'slow' early generation version.

So I got to thinking, is there anyway to dual boot my A1200? Have 4.1 for more "modern" stuff and 3.x (probably 3.9) for playing older games etc?

My thought on this is to have OS4 on the first partition and OS3.x on another bootable partition. Setting OS4 to have a higher boot priority and getting into 3.x using the early startup options to pick its partition to boot from.

Would this even work? Wanted to ask as I am waiting for a new higher capacity CF card to arrive but wanted to get the ground work done first :)

@smartroad

Yes, I did it on my A4000. Sometimes slipped with the timing and got the wrong kick in and had to cold reboot 10 secs to start again.

@smartroad

HI again! :D

My recommendation to dualboot os4.1 and os3.9 is to set os4.1 to the lowest boot priority.

Create a textfile in you kickstart drawer in os4.1 called BootDevice
In that te×tfile you just specify the name of your os4.1 partition. For example "DH1"

add a line to your kicklayout like this:

MODULE Kickstart/BootDevice

Poweron your amiga and select your OS4.1 partition as boot partition from the early startup screen and when the os4.1 kickstart is loaded it will use your os4.1 installation partition as boot device until you do a hard reboot.

Last edited by smf on 18-Mar-2017 at 06:27 PM.

@zipper

Wouw! I didn't know that was possible. It is a cool way to do it. But that way every time you reboot in OS4.1, you'll have to go to early startup.

I did it in my system (where I've installed both OS3.1, OS3.9 and OS4.1 on separate partitions) by making OS4.1 partition the only bootable partition and adding the following lines at the start of its startup-sequence.

Quote:

;BEGIN OS Selector DH0:C/Assign SYS: DH0: DH0:C/Assign C: DH0:C Assign T: RAM: Version exec.library VERSION 52 >NIL: IF WARN   Assign >NIL: LIBS: DH0:Libs/   Assign >NIL: ENV: RAM:   RequestChoice "Amiga 1200 OS Selector" "Please choose OS version to boot" " OS 3.1 | OS 3.9 | OS 4.1 "   SET OS $RC   Avail >NIL: FLUSH   Assign >NIL: LIBS:   Assign >NIL: ENV:   IF $OS EQ 1     Assign SYS: DH0:     Cd SYS:     Assign ENVARC: SYS:Prefs/Env-Archive     Assign Locale: SYS:Locale     Assign C: SYS:C     Assign S: SYS:S     Assign LIBS: SYS:LIBS     Assign DEVS: SYS:DEVS     Assign FONTS: SYS:FONTS     Assign L: SYS:L     Assign T:     Execute S:Startup-Sequence     EndCLI   EndIF   IF $OS EQ 2     Assign SYS: DH1:     Cd SYS:     Assign Envarc: SYS:Prefs/Env-Archive     Assign Locale: SYS:Locale     Assign C: SYS:C     Assign S: SYS:S     Assign LIBS: SYS:LIBS     Assign DEVS: SYS:DEVS     Assign FONTS: SYS:FONTS     Assign L: SYS:L     Assign T:     Execute S:Startup-Sequence     EndCLI   EndIF EndIF Assign SYS: DH2: DH0:C/Assign C: DH2:C DH0:C/Assign T: ;End OS Selector

Notes:
* As obvious I have OS3.1 on DH0:, 3.9 on DH1: and 4.1 on DH2:

* How it works:
- It first migrates the SYS: to DH0: (where OS3.1 is) to be able to use 68k AmigaDOS commands.
- Then checks the exec version.
- If it is higher than 52 (which means OS4.1 kickstart is already loaded) migrates SYS: back to DH2: and keeps on executing startup-sequence (which eventually boot up OS4.1 WB).
- If it is lower than 52, brings up a requester (using RequestChoice command) that asks which OS to boot.
- Migrates the SYS: to the partition in respect to users choice, and executes the startup-sequence there.

There is the "Killer App"

Instead of the Black&White a good point and click:

Which OS would You prefer today?

-Amiga

-PC

-xx whatever installed


" Good choice, loading in 5 seconds"

@alpyre

Having problems with both methods. The upshot is the same for both, I can get it to boot but after first boot it will report as DH1 (my 4.1 install) is not inserted/available.

Do I need to keep both under the 4gb limit?

@smartroad

How I have it set up is to split the first 2GB on the hard drive into 2 x 1GB partitions. 1 for OS3.9 and 1 for OS4.1FE.

its pita to set up and pita work with this. i have messed with this forever years ago and the final solution was afaik that i ve put the os3.x kickstart in the deneb flash, switching it on and off with the key on the a4000 box frontb resulted in switching the os on hard reboot. of course some check in the s-s was necessary, dont remember details , though. which all kinda almost reliably worked. but then i got tired of os4 and removed it altogether. problem solved.

@smartroad

My OS4.1 partition is only 1GB big. And it works flawlessly. OS4.1 uses 30% of it so it is more than enough.

Of course you can create bigger but always keep both system partitions inside the first 4GB's of the harddrive. Then I belive things will be ok.

Thanks for all the help guys, giving up on it. I need 3.1 more than I need 4 and none of the suggestions above have worked for me :(