Nezgar

Power LED in 130XE is sent through the keyboard Mylar... way down the line

Looks like the controller board from a Percom AT88 - SS SD drive. 40pin connector for standard floppy drives.. Wonder if it works, was replaced as defective, or upgraded to a double density/double sided controller in whatever drive box it came out of... Review here: http://www.atarimagazines.com/v2n8/productreviews.html And according to: http://www.atarimagazines.com/hi-res/v1n2/previews.php "The Percom "Doubler" requires no special tools to install and doubles the storage capacity of the AT88 from Atari. The retail price is $169.95. Percom also released its new family of double-density disk drives containing a parallel printer port. With these drives, you can attach a parallel printer to your Atari while by-passing the 850 Interface Module. The AT88-S1-PD is a single drive that retails for $529. The AT88-S2-PD is a double-drive that retails for $829." Picture i found:

Found the register page by watching the hover URLs http://www.atari.org.pl/forum/register.php may have to revert to google translate if you get stuck after that second link there works without a login

Wow, never noticed that before!

810 'bad' switch maybe slows the RPM so sector writes will corrupt/make bad sectors, to reproduce early copy protection. The red/black wires that are connected with a resistor may do this by increasing resistance on the line when switched 'on' 810 1/2 switch maybe is drive select, instead of setting the switches on the back. 810 unlabelled switch on far left may be a write protect/unprotect switch. 1050 same thing.. 0/1 maybe write enable/protect, and 1/2 a convenient drive # select. Do you have a pic of the inside of the 1050?

Do you mean the XF551 5.25" Double Sided Double Density (360K) drive? If so, they were fully produced and distributed. You can still buy one brand new in box from Best Electronics. Now hang on.. Interesting.... I've never heard of this until today, but I just googled it and found mention of it in the Atari 8-Bit FAQ. and a picture! So... probably single sided, SD and enhanced/1050 density, who knows about double density.

You beat me to it!

Does the RAMCharger add track buffering? I added an ATR of my "OSS DOS XL - ATARI version 2.35I2" disk that I have (without a matching drive) in a previous thread where where I inspected the interesting SKEW on the real physical disk, and listed out all the different skews that the formatter utility written in BASIC will do. The physical disk uses a standard Atari 9:1 skew on tracks 0-3, and then a 4:1 skew on tracks 4-39. http://atariage.com/forums/topic/104585-another-interesting-speed-comparison/?p=3759949

There is mention of this warmstart reset switch mod in the manual: 4) RESET mod: There is support for the hardware mod which hooks the SYSTEM RESET switch into the RESET line of the CPU. This is accomplished by inserting a 47 ohm resistor into the pads provided on the motherboard near CR103 and R183. A momentary switch to connect the resistor is also needed unless you wish to do a coldstart everytime SYSTEM RESET is pressed. With this mod and OMNIMONA! it is possible to recover from a system lockup. This is accomplished by pressing the momentary switch and pressing SELECT/RESET. This will pop into the monitor with the PC reflecting the instruction the CPU was trying to execute when it locked up (probably an illegal one). At that point RESET can be pushed by itself to do a normal warmstart.

not too familiar with PAL connections, but S-Video should work the same for NTSC, PAL, and SECAM. i think the only major difference would be the connectors. You may just need a cable/adapter that goes to SCART for instance instead of the 4-pin mini-DIN or separate Luma/Chroma RCA plugs.

Problem is that the Duplicator physically formats sectors 1-3 as 128 Bytes, rather than 256 and truncating the extra 128, which breaks most other drives density detection. Found the reference http://atariage.com/forums/topic/102644-1050-us-duplicator-identification-needed/?p=1252357 Not like Atari published a standards document for drive makers at the time. Percom paved the DD path, I guess this would be a pretty easy oversight to make... Solution is to just format DD disks in other drives I guess.

Great investigation Hias, very interesting! So purely educational at this point as it would be slower, but would there be any current way to use warp speed mode in spartados without first enabling USD emulation in v1? That would be an annoying 2 step process to get ultraspeed with Sparta, or most high-speed SIO software actually with a rev 1 rom. I wonder what degree of USD emulation existed in the happy 810 roms. Maybe nonexistant prior to rev 7. (warp speed only)

Good stuff Hias! Can you check: Can v1 still be bumped up to 56k using both the 'enable USD emulation' and 'enable fast writes' menu options as mentioned in the manual? If so, will the SDX INDUS.SYS perform both those settings as well? Lastly, does v1 still corrupt single density writes if USD Emulation is enabled, but fast writes are left disabled?

Now I'm curious to see a happy 1050 V1 in action to see if it really uses a slower SIO speed natively... that version is probably pretty rare. All my happy boards have soldered on roms or eproms, so not an easy thing to swap. I've also not seen a happy 810 in action. The lower SIO speed should exhibit there too at least prior to V7. Likely in the 38400bps range. It may be the same speed I hear used in the happy backup utility.

Man that paragraph is hard to follow... implies the two roms are named Rev 2 (the older one) and Rev 7 (the newer one). And last sentence 'not fully compatible' is the implied reference to the corruption, to not use it without write buffering. Edit: reading it again, 7 is the older original ROM, and had supposedly a slower 'warp speed' SIO speed compared to USD ultraspeed. 2 is newer, and defaulted to the faster SIO speed (so the enable USD Emulation menu option would essentially have no effect) but manual enable of fast writes would still be necessary for both. (to be 'fully compatible' as per happy, read: to not corrupt byte 3 of single density sector writes)

Ok, true. I guess I meant 'currently' the only way haha

Maybe it's like SpartaDOS SCOPY - I think it only 'compresses' empty sectors...

Yep. Boot up with SpartaDOS 3 and do some writes to a single density disk I guess I never ran across this back in the day because I primarily used SpartaDOS X, which the ICD versions include 'INDUS.SYS' in the default config.sys which reprograms happy drives properly to highspeed with fast writes which avoids the issue. The current SDX 4.48 I'm using doesn't include INDUS.SYS in the default config.sys so it's also easy to reproduce if I forget to manually load it. I guess back in the day I never wrote to disks with SpartaDOS 3 because I would only drop out of SDX to run BBS Express 5, and the custom SpartaDOS 3.3 for the BBS didn't do high speed SIO at all I think, which saved a few bytes of RAM. (perfectly fine when you're running purely from MIO hard drive and RAM disk) Also, I would have been primarily working with double density disks for backups from the hard drive, which also would have avoided the issue ... I noticed lately there's also a vague reference to this corruption bug in the happy 1050 manual itself, and the MyCopyR! Sector copier release notes mention one revision that will now always enable fast writes rather than make it selectable to workaround the bug in happy drives. I'll have to dig those up and quote them here later

There is specific mention of this in the Happy 1050 manual. You can tell what version you have, diagnostic test will show 'PASS' for v1 and 'Pass' for v2. The 'ultraspeed emulation' is a bit of a misnomer... it will enable fast buffered reads, and non-buffered writes, but I wish they almost didn't add that feature because writes to single density disks in this mode will corrupt byte 3 of every sector written. Disk formatting will also still result in the normal 9 sector interleave, and not the USDoubler interleave. Full USD Emulation, with USD skew format support is only posible on a happy drive by using Steve Cardens HAPPY.COM utility included with RealDOS. It literally uploads the USD rom to the happy RAM and executes it. It will be a true USD until powered off.

Stock unmodified Atari DOS 2.0 and 2.5 Only support 2 drives. there are some memory pokes you need to do, and re-save dos files to disk to get it to support up to 8 drives. Memory usage for buffers and such back in the day was a big deal, so they shipped it with the most common configuration. If you switch to SpartaDOS, it will support at least 8 out of the box... And i found the article! http://www.atarimania.com/faq-atari-400-800-xl-xe-how-do-i-modify-atari-dos-to-support-more-than-two-drives_62.html

gYours, the one in the top right, I think was the one that originally came with the 130XE (at least with mine). It served me well running a BBS for 10 years 24 hrs a day with no issues, and i still have it. The nutorious 'Ingot' - the one in the top row middle is the one that has gone bad and taken many people's machines with it.

Dropcheck has reimaged the classic ICD RAMBO XL 256K upgrade here for $25 and its actually still available, a little bit of soldering. No RAM chips included, but they can be found on eBay : http://www.bitsofthepast.com/?product=reimaged-rambo-xl-adapter It would give you the 64KB of 130XE compatible RAM, plus another 128. Largest ramdisk would be 192KB. Antonia 4MB is likely still available if you PM Simius. As mentioned already, both of those don't really give you anything more than RAM, which is where the U1MB shines for the extra features if you are so inclined.

Hmm random thought I'll have to check out later... I seem to remember you can renumber happy drives in the utility menus. if it lets you renumber to 5-8 then in theory you could get 8 happy drives online with unique drive ID's.... i wonder if the multidrive backup supports drives above #4... stay tuned lol

Oooh, now that is interesting! So the next logical step is to allow Altirra to use 10502PC to talk to real SIO devices! Then you can use archiver to copy from an ATX virtual CHIP drive in D1 to a REAL CHIP drive in D2!

I thought the 810 MicroSD SIO2PC was pretty funny. http://hackedgadgets.com/2011/05/07/mini-atari-810-floppy-drive/