Apple II

Hello All, 

I just received a IIGS ROM1, it has a memory card and no floppy drive or hard drive or ...

When I start it, it says Check Startup device...

I tried by adding a Apple IIe Disk controlleur and boot from a PRODOS Floppy but nothing changed. 

Is there somewhere I can get basic knowledge on how a IIGS is working ? 

What should this machine be equiped with ? 

I need to changed the internal battery, it seems to be soldered :( what is the best option, what is the reference of the battery ?

Hello, hoping someone can set me on the right path, my knowledge is limited as the las time I played with an Apple II I was a student in Jr. High in the computer class run by Mrs. Quigley.  A bit of backstory in case it'll help.  A B&H Apple II came to me with a dead power supply, and only one ROM CARD 600 in it.

I tried repairing the power supply with a capacitor kit but was ultimately unsuccessful.  I ended up getting a replacement PSU from ReActive, and that got the Apple II booting up to a garbage screen to the monitor prompt.

I have two 800K 3.5" drives and one 5.25" drive for my Apple IIGS. However, I can't seem to use any 800K 3.5" disks. It's like it can't find it, or it doesn't work, and I've tried both 3.5" drives. I even tried just having one 3.5" drive connected, and no other drives, and it still wouldn't see or load anything from any of the disks.

I have a Microsoft Softcard III CP/M card with the manuals and disks in original box that i want to sell.

Obviously i know the card can't be used, but can my Enhanced //e with Disk ]['s or DuoDisc (i have both) read Apple /// disks to verify there's still something on them?

I recall reading this somewhere online recently, but wanted to confirm before i try it and possibly destroy the disks.