Caterpiggle Posted November 22, 2014 Share Posted November 22, 2014 (edited) Hello Sup8pdct, That item had been sold to the buyer just a few hours. D48 application for PC ? I recently checked web site for "D48" application, would not find on web sites. Please more specific full number included version number. It would be help. Edited November 22, 2014 by Caterpiggle Quote Link to comment Share on other sites More sharing options...
Defender II Posted November 22, 2014 Share Posted November 22, 2014 (edited) This is a facinating topic and piece of Atari history. Just a few questions to see if making a MOD kit for SF354's or SF314's would be possible... Hello Jon flashjazzcat, on 10 Nov 2014 - 12:40 PM, said: Someone needs to clone that controller board so we can mod our otherwise useless ST floppy drives. Dropcheck? Sincerely Mathy PS I read on her site that's she's back in business. And she could add the second SIO port. Yes, someone making PCBs would be great use for the ST drives out there to convert them to 8-bit use rather than changing our XF551's! Even modifying the controller PCB to handle DS-DD for ST SF314's in stead or just copy it and make MOD kits for SS-DD for a ST SF354's mod kit. I think the expectation is that we can learn what command puts it into DD mode. That would give us a 320K drive. Obviously, engineering wasn't quite done with the design... not ready for PrimeTime at the FCC. This is really a collector's item - you shouldn't hack it. Bob I agree, but fixing the ROM so we could modify SF354's would be great! Quick look at the code, it has commands R, r, P, W, S, !, N, O, H, ". There a couple of others but am going to bed as am falling asleep at keyboard. will try and figure out what some do latter. James The other 3 commands are R, P, W with high bit set. It doesn't appear that high bit set means anything at this point. The H command appears to set high speed sio, a similar speed to the XF551. All bytes sent/returned after the H command is issued with a $01 in one of the aux bytes will be at high speed except for the command frame. Once high speed is set, Instead of A (ack) returned for command Acknowledge, a H is returned. To turn off, issue a H command with 0 in aux bytes. A custom dos required for this baby. James How hard would it be to patch the ROM so it doesn't need a custom DOS if we wanted to make a mod kit for SF354's? Digging a bit more, it appears the full single sided 80 track disk is treated as a double sided 40 track disk. Also the percom block can return either 26, 18 or 16 sectors per track. Need to dig more to see which densitys do what. The percom block aux byte returns $48 (H) if in high speed mode or $41 (A) in normal speed mode. The XF551 returns $41 always. James Edit: It won't work on PAL computers. The sio routines are not patched. "the full single sided 80 track disk is treated as a double sided 40 track disk" Do you think that is to keep be compatible with the XF551 for the software already out there as Bryan suggests? How does that compare with Could the ROM sio routines be patched so we could modify SF354's for PAL 8-bitters as well? Wow, that's kinda clever as it would have made it completely compatible with software for the XF551. Bob. Could you please try to format a disk DS DD 40 tracks, 16 sectors per track. This should get a working format of 1280 odd sectors with the XF351. The single density format you done, does dos think it was successful but it wasn't? Only way to tell is to read beyond sector 720 and see what happens. James Bob were you able to test beyond sector 720 to see if it really was successful? Edited November 22, 2014 by Defender II Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted November 22, 2014 Author Share Posted November 22, 2014 After a SD format, I can read out to sector 1280. What is the advantage to starting with an XF351 rather than an XF551 if we want to make an 8-bit drive out of an SF354? If you use an external power supply, there isn't much left of an XF551 to fit into the SF354 case, is there? Bob Quote Link to comment Share on other sites More sharing options...
R4ngerM4n Posted November 22, 2014 Share Posted November 22, 2014 Wow, it's gone for $1800. Quote Link to comment Share on other sites More sharing options...
sup8pdct Posted November 23, 2014 Share Posted November 23, 2014 I found D48 hidden in here. http://cd.textfiles.com/psl/pslv2nv06/PRGMMING/DOS/ASM/ as part of another archive. Where i originally got it from, i cannot remember. attached is D48. run from winblows command prompt or dosbox for PC James d48.zip Quote Link to comment Share on other sites More sharing options...
TXG/MNX Posted November 24, 2014 Share Posted November 24, 2014 Hi, The XF351 has the same cpu as the XF551 does this mean when I burn this rom and connect a 3.5" my XF551 I got a XF351 ? Quote Link to comment Share on other sites More sharing options...
sup8pdct Posted November 24, 2014 Share Posted November 24, 2014 The code is very similar with all 8040 pins appearing to have the same function between the 2. My guess is the XF351 was done first then the XF551 was done latter using the code from the 351 as a start point. Many routines are the same, some even in the same location. So i would say yes. BUT, it wont work on PAL computers. James Quote Link to comment Share on other sites More sharing options...
TXG/MNX Posted November 25, 2014 Share Posted November 25, 2014 ? Why doesn't it work on PAL.. Quote Link to comment Share on other sites More sharing options...
sup8pdct Posted November 25, 2014 Share Posted November 25, 2014 Its sio code is same as early xf551. It wouldnt work on pal. Atari patched the code to make it work by adding one machine cycle to the timing routines. I can show you if you like. James Quote Link to comment Share on other sites More sharing options...
TXG/MNX Posted November 25, 2014 Share Posted November 25, 2014 Yep show us pleaze 1 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted November 25, 2014 Share Posted November 25, 2014 Pretty much drop in a rom and replace the mech, That's what I have on the top of my stack a 3.5 XF hack. Quote Link to comment Share on other sites More sharing options...
+Larry Posted November 25, 2014 Share Posted November 25, 2014 If someone tries this rom transplant, please let us know how it does. I suspect there are better XF 3.5" alternatives (such as Hyper-XF). The best I've used is the CSS/Puff one- and two-drive conversions. (Actually the best is the Floppy Board, but that doesn't count.) Would an XF551 pcb fit into an SF314/354 case? Dropcheck's? I've got an "XF2" pcb that I need to check, but my guess is -- too wide. -Larry Quote Link to comment Share on other sites More sharing options...
pixelmischief Posted November 25, 2014 Share Posted November 25, 2014 Would an XF551 pcb fit into an SF314/354 case? Dropcheck's? I've got an "XF2" pcb that I need to check, but my guess is -- too wide. It does not fit. I have been waiting for this for years and on occasion bang on the hardware gods for a miracle. MetalGuy and Candle in particular. I've also been in contact for a couple of years with a guy here about something called an XF551B board that would fit, but he's had RL to deal with. Picture below. Quote Link to comment Share on other sites More sharing options...
+Larry Posted November 25, 2014 Share Posted November 25, 2014 Thanks. Too bad, but I suspected it. Also unfortunate that Dropcheck didn't have input early enough to possibly make a board that would fit in either style case. But even if it did fit, there is the problem with the round vs. trapezoidal connector openings. Would have taken some "body work" to get it usable. -Larry Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted November 25, 2014 Share Posted November 25, 2014 (edited) I thought someone in the US had built an XF551 board that was maybe 1/3 in size that replaced the same board in an XF551 case. It would probably fit into the SF. I just can't remember where I saw it. Something about XF551 re-imagined .. Edited November 25, 2014 by kheller2 Quote Link to comment Share on other sites More sharing options...
+Larry Posted November 25, 2014 Share Posted November 25, 2014 You might be thinking of this? http://www.bitsofthepast.com/?product=reimaged-xf551-disk-drive-controler-wmodern-power-supply But the width looks to be the same, even though the length might be less. -Larry Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted November 25, 2014 Share Posted November 25, 2014 You might be thinking of this? http://www.bitsofthepast.com/?product=reimaged-xf551-disk-drive-controler-wmodern-power-supply But the width looks to be the same, even though the length might be less. -Larry Yeah that's it. It might fit sideways.. didn't know we were looking for an elegant solution. Quote Link to comment Share on other sites More sharing options...
sup8pdct Posted November 26, 2014 Share Posted November 26, 2014 Below is a small snippet of code from similar locations in each rom. Apart from address difference of the 351 code , It does the same thing. XF351... mov a,#80h nop nop nop nop jf0 X025f nop nopX024c: nop nop nop jf0 X025f nop nop nop nop nop nop nop nop nop nop nop nop nop nopX025f: clr cXF551 1st version, worked for ntsc, not PAL mov a,#80h nop nop nop nop jf0 X0259 nop nopX0246: nop nop nop jf0 X0259 nop nop nop nop nop nop nop nop nop nop nop nop nop nopX0259: clr cXF551 Patched to work on PAL MOV A,#80H NOP NOP NOP NOP JF0 A259 NOP NOPA246 NOP NOP NOP JF0 A259 NOP NOP NOP NOP NOP JMP A2EE NOP ;never gets hereA253 NOP NOP NOP NOP NOP NOPA259 CLR C " "A2EE JMP A253 " As you can see, the PAL version (which works on ntsc as well) has a JuMP to end of that pages code then jumps back. The affect is to add one machine cycle to the timing of receiving of each bit. There are 3 locations where one machine cycle had to be added. The above code is 1/2 of what is used to receive data frames. Command frames use very different code but it too has been patched to add in one cycle. James Quote Link to comment Share on other sites More sharing options...
sup8pdct Posted November 28, 2014 Share Posted November 28, 2014 (edited) Digging through the code more, It would appear the format code and sector divide for read/write is fixed at 1280 sectors, 16 sector per track, despite status bits supporting 26 and 18 sector per track and support for 128/256 byte sectors. Wondering if it is work in progress and this is a proof of concept version. James Edited November 28, 2014 by sup8pdct Quote Link to comment Share on other sites More sharing options...
Defender II Posted January 23, 2015 Share Posted January 23, 2015 Digging through the code more, It would appear the format code and sector divide for read/write is fixed at 1280 sectors, 16 sector per track, despite status bits supporting 26 and 18 sector per track and support for 128/256 byte sectors. Wondering if it is work in progress and this is a proof of concept version. James It is great that you have been able to dig into the code and figure these changes out. Do you have a copy of the anotated XF551 code for the ROM from Atari? I remeber some thread that mentioned they had it but lost it due to a mishap, but I can't find the thread anymore. I am still interested in getting an ST drive and modifying it to work with the 8-bits. I like the smaller cases and don't want to modify any of my XF551s. Quote Link to comment Share on other sites More sharing options...
sup8pdct Posted January 23, 2015 Share Posted January 23, 2015 check out this thread http://atariage.com/forums/topic/161319-disassembly-particularly-i8040-mcs48-architecture/?hl=%2Bxf551&do=findComment&comment=2825432 james Quote Link to comment Share on other sites More sharing options...
hueyjones70 Posted July 16, 2019 Share Posted July 16, 2019 (edited) It appears that this topic evolved into the Idea:external ST Drive... . Edited July 16, 2019 by hueyjones70 Quote Link to comment Share on other sites More sharing options...
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