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#3942645 Dumb Question OTD: Preparing CF Media for APT Partitions

Posted by flashjazzcat on Yesterday, 7:13 AM

Not so weird, but my bad for not telling you that you need to specify the path as well. So A:>FDISK.COM will load the partition editor from drive 1. This is just the way SDX works. You can fix the SDX ROMs by setting the hidden attributes on the three FDISK*.OVL files. The native SDX OVL files on CAR: all have the hidden attribute set (to avoid cluttering up the directory listing, I guess) and I merely followed suit, but it caused more trouble than it was worth by the looks of it. :)

#3942588 Dumb Question OTD: Preparing CF Media for APT Partitions

Posted by flashjazzcat on Yesterday, 4:21 AM

Isn't an APT partition limited to 32MB? Or can you technically make larger partitions even though SDX is limited to 32MB.


APT partitions can conceivably be 128GB in size, although - as you say - SDFS will only see the first 32MB. In fact I never attempted to format a partition larger than 32MB from the SDX formatter, so I'm not entirely sure how it would react.


One way to use much larger partitions is via the aforementioned "external" partitions: APT entries which are actually links to FATs outside of the APT. When the SDX FAT drivers are R/W, this will be a great way to move data back and forth between the A8 and the PC.

#3942585 1088XEL Atari ITX Motherboard DIY Builders Thread

Posted by flashjazzcat on Yesterday, 4:17 AM

Are there specific hooks built in to the new firmware and how many rom slots will the JAZZ GUI take up?

The new firmware (since June 2015) has included support for 1KB plugin modules, and there are hooks for writing to hardware, adding menu items, reacting to menu edits, etc. This approach was devised in order to avoid hard-coding the functionality of the four general purpose IO signal headers, and with the 1088XEL it enabled easy reassignment of the pin previously assigned to Covox, as well as new functionality on signals S0 and S1. I still had to customise the main BIOS code for the 1088XEL, however, since we wanted a special splash-screen and some unique behaviours on cold power-up.


As for the GOS: It requires 128K, or 16 ROM banks. This intrudes on the last 64KB originally allocated for SDX; hence provision is made for shrinking the SDX slot and flashing the 192KB ROMs which are now available. For those with no interest in or need for a WIP GOS, one can also enlarge the SDX slot to 320KB, providing ample room for more stuff on CAR:. :)

#3941989 Name that program: Enhanced font dot-matrix text with 1/144th line feed

Posted by flashjazzcat on Mon Jan 22, 2018 12:45 PM

Daisy dot II - vaguely remember I had a copy of that! Could it interpret AtariWriter+ files?

It could handle the output of any Word Processor capable of printing to disk. You'd insert the DD-II formatting codes (preceded with a backslash, IIRC), print the file to disk, then DD-II took over. The drawback was that DD-II had no control over line-breaks or pagination, so you had to plan ahead regarding font pitch and line length, etc. Daisy-Dot III promised to deal with those issues via a built-in text formatter, rendering the word processor's printing functionality redundant. I guess print previews and managing pagination in the WP would be a little more difficult, but in any case I never got the chance to try out DD-III since I'd gotten rid of the dot-matrix printer by then and the Atari followed not long afterwards.

#3941256 Name that program: Enhanced font dot-matrix text with 1/144th line feed

Posted by flashjazzcat on Sun Jan 21, 2018 5:24 PM

Daisy-Dot II.

#3941010 Diamond GOS 3.0

Posted by flashjazzcat on Sun Jan 21, 2018 12:57 PM

@FJC have you seen QTop the sinclair desktop at any time, would any of it's ideas help?

I hadn't seen that one, but I've seen Doors and just about every other 8-bit GUI floating around. ;) As I mentioned, many of them present some kind of desktop metaphor which simply allows you to run legacy software with a few clicks, or are written in BASIC and thereby impose the limitation that every single GUI application has to carry the entire UI library along with it (and multitasking is entirely out of the question). For inspiration and ideas, one need look no further than SymbOS, and to set one's sights any lower at this stage would likely result in another desktop launcher.


The obstacles in the way of completion have less to do with a lack of ideas or solutions than a lack of hours, choosing the right approach to a given problem, and the difficulties presented by development tools (or the lack thereof). MADS's proprietary relocatable file format was never intended for the development of stand-alone applications (it appears to have been wholly aimed at the linker), and yet I chose to re-purpose the format for the production of GOS apps. It works quite well, but does not allow more than a single segment per file, meaning that it's impossible - for example - to write SDX-style driver modules with one absolute segment, a relocatable main memory segment, and a relocatable extended memory segment, with fix-up tables indexing all three. Of course, these limitations can be worked around, but every solution selected involves difficult compromises.

#3940956 XEL-CF Compact Flash Adapter for 1088XEL (formerly XEL-I3)

Posted by flashjazzcat on Sun Jan 21, 2018 11:55 AM

Only limitation is imposed by 28-bit LBA, so in theory you could use a 128GB card. :)

#3940926 XEL-CF Compact Flash Adapter for 1088XEL (formerly XEL-I3)

Posted by flashjazzcat on Sun Jan 21, 2018 11:25 AM

FAT: as big as the file system allows. APT: currently SDFS partitions are limited to 32MB each, so there's no point in making the APT bigger than 100MB or so if you want a few partitions (although you might allocate more for future expansion). SDX provides a read-only FAT driver which you may use to access "external" partitions, which are created in the APT but link to existing FAT partitions outside of that space.

Note the FAT loader on the new firmware supports 250 long filename entries per folder (all instantaneously alpha sorted on reading), so you'll want to employ a sensible folder structure which you can then recursively search if desired. The loader also supports multiple FAT partitions so there's a lot of flexibility as to how you can organise space. ;)

#3940762 1088XEL Atari ITX Motherboard DIY Builders Thread

Posted by flashjazzcat on Sun Jan 21, 2018 7:17 AM

This is why I literally put my 9V AC PSU at the other side of the room prior to powering up my 1088XEL for the first time. It's also the reason I fitted a standard 7-pin DIN to the 1200XL I modded for 5V DC (someone asked later "What was wrong with the original connector?"). This is why.

#3939193 1088XEL Atari ITX Motherboard DIY Builders Thread

Posted by flashjazzcat on Fri Jan 19, 2018 7:43 AM

You could pre-heat the board with hot air if the iron is struggling. I was working on an HP laptop the other week (probably a ten layer PCB or something) and it took ten minutes of hot air at 450 C to get a shorted mosfet off the board. :)

#3939183 1088XEL Atari ITX Motherboard DIY Builders Thread

Posted by flashjazzcat on Fri Jan 19, 2018 7:10 AM

Cool - I just wondered, since you'd mentioned that the 1088XEL PCB was sinking a lot of heat and impeding solder flow. Definitely don't reduce the heat: I have mine stuck at the same temperature on a permanent basis and it works great with 60/40 solder.


I actually had to correct a backwards LED on my XEL-CF a few weeks ago and even that little board didn't present any problems when it came to removing solder. Flux will definitely help. Most of the time I use a tip with a flat 45 degree bevel (not sure what the proper name is), and resting the flat of the tip on the via for a second or two with a spring-loaded solder pump on the other side gets the job done. Anything which doesn't want to cooperate gets coated in flux and wicked clean. :)

#3939174 Diamond GOS 3.0

Posted by flashjazzcat on Fri Jan 19, 2018 6:57 AM

Expect progress on my GOS project this year. Unfortunately early in 2015 - while working on the GOS project - I required changes to the U1MB BIOS in order to boot the GOS ROM, and to that end did a ground-up rewrite of the firmware for U1MB and Incognito. Having given that to the community I felt somewhat obliged to keep debugging and developing it, and here we are nearly three years later with the final "v2.0" alt firmware release pending and the same custom firmware powering U1MBs in the 1088XEL motherboards. There's also more hardware on the way which will require versions of the new loader, etc. I very much enjoy the firmware development side of things, but lack of progress on other projects is as frustrating for me as it is for others. But all adults are hopefully able to comprehend the necessity of time management and prioritisation.


Regarding Diamond: I did indeed download and scroll through the source code a couple of years ago but aside from admiring the clever mouse sampling and simply marvelling that Alan was able to get the GUI as good as it was at such a young age and without today's development tools, it's not something I would devote time to developing having already gotten half way through developing a multitasking graphical OS. I was in discussion with Alan regarding further development of Diamond before I even started work on the multitasking GOS, but unfortunately he went silent for a while and the promised source code never arrived, so I went off and started from scratch. The Diamond source suddenly appeared on the forum a few years later.


I have no intention of trying to make my OS run in 48K (or 64K, for that matter: you'll need 128K), so the only stock machine it'll run on is a 130XE, and the 128KB code base requires a banked ROM. There are quite a few "desktop metaphor" systems for the A8 which fit the bill if all you want to do is launch existing software using icons and drop-down menus.

#3935212 Cases for the Mini-ITX based Atari 8-Bit Motherboards

Posted by flashjazzcat on Sun Jan 14, 2018 4:13 PM

Best PM admin if you want an edit to a topic title.

#3934564 1200XL Mysteries (Continued)

Posted by flashjazzcat on Sat Jan 13, 2018 3:27 PM

I might be (and probably am) wrong, but is it possible chroma was left off the monitor jack to ensure compatibility with the older C64 monitor jack (and thereby cables)?


As to the other oddities, I guess Atari initially wanted to keep the 9V AC PSU which powered the 800, disk drives, etc. Joystick port angle actually seems perfectly reasonably to me and saves a little (very little) horizontal space. As for the multiple ROMs: I think splitting the OS across more than one chip was fairly common at the time. The fact is, the dual sockets neatly provide for an internal BASIC modification, so it's a positive in that respect.

#3933722 1088XEL Atari ITX Motherboard DIY Builders Thread

Posted by flashjazzcat on Fri Jan 12, 2018 12:46 PM

Quick question regarding the XEL-CF-][ ... how fast is a CF-to-memory copy ? And how fast is a CF-to-CF copy ?

Just did a quick (and rough) test here copying a 720KB file from a 512 bytes/sector partition on one card to a 512 byter on another card and it took around thirty seconds.

Read speed off the disk is about 65KB/s including file system overhead.