Adam, thanks for those. They are a big help!

Hi Adam,

I agree with you. Tor got me to look at it all again. IMHO, the simplest build would be the demo spinning cube program.

The USR routine for Merlin is there too. A complete Apple native build is possible, assuming one has a real floppy drive. :)

An update: I've studied DOS and have been ...

Update:

A long discussion on assemblers and some education on my part has advanced the project some. It's time to build up a sample bootable Apple disk image and check it on both a real machine and emulation. I'll start with the very basic example Miles provided, then move to one that incorporates ...

Well then it was likely just missed. To build that on anything but a real Apple would require a real disk drive emulation. There is a small demo program there that will load a picture. One could build up the core routines, init a disk and give it a shot. I'll pass, but it's good to know anyway.

@Bitwise: :) Which assembler is that? as65?

@Tor: I saw that code too. You might be right about it. If somebody wants to attempt the Apple native build... I setup with Merlin in D1, a PRODOS hard disk to hold the code, and D2 is the drive used to hold the finished program. I only have one drive ...

I don't have a "system" yet. That's what the feature / function discussion is all about.

Yes, Merlin used a DOS for everything but the output to the disk, which was done on the 18 sector RWTS.

Re: 16 sector. There isn't as much space. Right now, two sides are required at 18 sectors. This will ...

@whartung: I've no intention of building on the //e To be honest, that's brutal. I have explored the code on the //e to learn how things were done then, and doing that helped to understand how the thing works on basic levels, and it will prove to be a reference later on too.

The plan is to build ...

Completely agreed on the financials. Packing it onto one disk was actually cited as a strong point in the journal JM put out there to read.

Efficiency was also cited. Disks held more and were fast, due to that RWTS code being very good code.

@TeamTempest: Oh, and I just noted this: "even without using that ability to think outside the address space so many assemblers lack."

Can you cite even one that can? I looked really hard. :)

Sorry to be difficult. I don't mean to be. And I'm compelled by the fact that every other piece of ...

To be really clear, PoP refers to tracks and sectors when it access it's disk. What it does specifically is request that a given track and sector list be read into RAM at a specific address. That's it. The RWTS performs that task and only that task. A DOS for the Apple would overlay on top of that ...

Seems to me a few things are mixed together here.

There is what happened then. What happened then was code got assembled to RAM, and got written out to 18 sector disks, and it was written track and sector with a small routine called by the Merlin assembler. There was no DOS for the target media ...

I'm Doug, BTW. I like my username, but it can be goofy in conversation sometimes. Hi Garth.

Well, I wrote it wrong: RWTS = Read Write Track Sector. It's the core bit of code needed to interact with the Apple ][ disk drive. The drive is a software driven device, with only a little bit of hardware ...

Yes, that is roughly it. I've read through enough to understand that. The process would not have gotten rid of DOS or PRODOS though. That's needed to fetch the assembler and code from ordinary disks. At one point, JM had a hard disk and floppies. PRODOS remans resident to work from, while the 18 ...

@Electric_Eye: Can you link me to, or write up a rough example?

Something really simple, like one or two instructions set to run at a 64K friendly address, say $2000, but assembled to $13000 and saved. It doesn't need to be complete, just that one capability highlighted would be great!

@All ...

Yes. Precisely. What I found interesting was I found no assembler that would allow for a large memory arrangement. They all wanted to manage banks, segments, etc...

So far, this has been a great exercise! I've learned a lot. It bothers me considerably that I cannot find an assembler that does it ...