AtariGeezer Posted April 25, 2017 Share Posted April 25, 2017 This is what I have at the moment. There are incomplete connections, if you find an omission or correction, please post it I've added links to the pics that Mr. Atari posted for you to check... Jay 7 Quote Link to comment Share on other sites More sharing options...
Kyle22 Posted April 25, 2017 Share Posted April 25, 2017 I wish I had some info for you, but I LOVE the fact that you are doing this! It has always been my dream to see the XLD live again. 1 Quote Link to comment Share on other sites More sharing options...
Dropcheck Posted April 25, 2017 Share Posted April 25, 2017 Just doing a cursory glance, it looks like a 1050 drive circuitry, minus the power supply plus some PBI glue logic. Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted April 25, 2017 Share Posted April 25, 2017 Is this one different from the "jaysmith2000" one? I can't find the original thread and pics from 2007, but have these... 2 Quote Link to comment Share on other sites More sharing options...
Dropcheck Posted April 25, 2017 Share Posted April 25, 2017 Is this one different from the "jaysmith2000" one? I can't find the original thread and pics from 2007, but have these... post-5-1148098130.jpg post-5-1148098094.jpg post-5-1148098082.jpg This looks like it could be a hand drawn schematic of this board. I don't know where I got this. The file was buried in a folder that had all sorts of bits and pieces on the 1400 - 1450 computers. 5 Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted April 25, 2017 Share Posted April 25, 2017 The TONG board is different from the 1400 and 1450 boards. But the circuits might be similar for the drive. Quote Link to comment Share on other sites More sharing options...
AtariGeezer Posted April 25, 2017 Author Share Posted April 25, 2017 (edited) This looks like it could be a hand drawn schematic of this board. I don't know where I got this. The file was buried in a folder that had all sorts of bits and pieces on the 1400 - 1450 computers. That's what I was referring to in the PBI R: Fi Project thread, it's similar but not the same. I think this site is where I found all the 1450xld (Tong) hand drawn schematics back in 2011... There are other atari floppy drive schematics that use the WD2797 FDC and 8048 family MCU like the SN360 and Toms 710. The Toms 720 also has the 8155... Edited April 25, 2017 by AtariGeezer Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted April 25, 2017 Share Posted April 25, 2017 What confuses me is that I have never seen any drawings for the TONG, let alone Hi-resolution pictures of the board. Since the TONG board had additional devices on it, I assumed this schematics were of the short boards. I could be wrong, and most likely am, but I never did a study as to what FDC was used on which version of the 1450s. Also, the U numbers on those schematics do not match the 6/8/84 TONG parts list locations for X1A. Again, everything could be wrong given how many prototypes there were... and maybe these are accurate later TONG designs. Quote Link to comment Share on other sites More sharing options...
Dropcheck Posted April 25, 2017 Share Posted April 25, 2017 Is this one different from the "jaysmith2000" one? I can't find the original thread and pics from 2007, but have these... post-5-1148098130.jpg post-5-1148098094.jpg post-5-1148098082.jpg So what version do you think this is? It looks like a fully functional version. I'm somewhat a novice of the various versions of the 1400 series. In general I know that the 1400XL was a successor of the 800XL. But not much more. Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted April 25, 2017 Share Posted April 25, 2017 Ignoring what the pretty silver marketing label says, you have this motherboard progression: 1400->1450->TONG (toss the 800XLF and the 130XE:128K 800XLF in there too, 900XLF, then 130XE) The 1400 and 1450 are almost identical, the 1450 having the bus header for the drive. From what I can tell, the 1400 is just a very early version of what became the 1450 board. TONG was what came from the scrapping of the 1400XL and basically starting over. I of course defer to the usual specialists for Atari history. Quote Link to comment Share on other sites More sharing options...
+kheller2 Posted April 26, 2017 Share Posted April 26, 2017 So it looks like both the Mr. Atari and the TONG ones are very similar. Both use SA400 interfaces, 8040/8048 CPU. The Jay doesn't look like SA400, but looks like standard 1050 mechs of some sort.. but is using the same ROM as the Mr. Atari? Confusing. The amount of RAM possibly varies. Quote Link to comment Share on other sites More sharing options...
mr-atari Posted April 26, 2017 Share Posted April 26, 2017 This is what I have at the moment. There are incomplete connections, if you find an omission or correction, please post it I've added links to the pics that Mr. Atari posted for you to check... Jay 1450-PDD-Wiring.gif I have also dumped the roms. :-) Shall I upload or pm them..... Quote Link to comment Share on other sites More sharing options...
AtariGeezer Posted April 26, 2017 Author Share Posted April 26, 2017 (edited) I have also dumped the roms. :-) Shall I upload or pm them..... Are they different from this post ? I first found some at atarimuseum.com when I was looking for info on the 1450... Edited April 26, 2017 by AtariGeezer Quote Link to comment Share on other sites More sharing options...
mr-atari Posted April 26, 2017 Share Posted April 26, 2017 Totally forgot about that thread...... Long time ago for me already. Nice machine I have borrowed from them, pity I could not keep it :-P No, they do not differ. Yes, they are the same. That was the dumps I made and uploaded. Quote Link to comment Share on other sites More sharing options...
AtariGeezer Posted April 26, 2017 Author Share Posted April 26, 2017 Ahh, okay. Yep, if I had been more observant then, I would have asked you to take 2 more pics to make better sense of the grouped wires at U9 and U14 But hopefully with some help from other users here, we can made a good schematic... Quote Link to comment Share on other sites More sharing options...
mr-atari Posted April 26, 2017 Share Posted April 26, 2017 I checked my pictures, but the one you have is what I got. I did find 2 screenshots when you boot normally or with SELECT down. Not sure if I posted them in the original thread. I did some bench-marking back then with RWTEST.XEX But results were rather disappointing for a parallel drive. Success with the project ! :-) Quote Link to comment Share on other sites More sharing options...
AtariGeezer Posted April 28, 2017 Author Share Posted April 28, 2017 Thanks for checking on that... 1 Quote Link to comment Share on other sites More sharing options...
Kyle22 Posted April 28, 2017 Share Posted April 28, 2017 . . .I did some bench-marking back then with RWTEST.XEXBut results were rather disappointing for a parallel drive. . . . Did you try different sector skews? Skew greatly affects speed. Quote Link to comment Share on other sites More sharing options...
mr-atari Posted May 5, 2017 Share Posted May 5, 2017 No, I did not, I remember. But the speed was about the same as a 1050. I was expecting speeds 5-10 times faster (serial -> parallel). But didn't..... Quote Sat Jan 17, 2015 10:49 AM "RWTEST on the PDD: 411 B/s write and 1170 B/s read, that is a bit disappointing." Quote Link to comment Share on other sites More sharing options...
ijor Posted May 5, 2017 Share Posted May 5, 2017 No, I did not, I remember. But the speed was about the same as a 1050. I was expecting speeds 5-10 times faster (serial -> parallel). But didn't..... As Kyle22 is saying, sector skew is critical. If you use the normal 1050 skew, the drive will need to wait until the rotation puts the next sector under the head anyway. That depends only on the RPM disregarding how fast the parallel interface transferred the sector. So the faster transfer speed gets mostly spoiled except with software that uses a smart, out of order, sector reading to compensate. 1 Quote Link to comment Share on other sites More sharing options...
+Nezgar Posted September 12, 2018 Share Posted September 12, 2018 I'm very curious to hear the results of different skews with the PBI disk drive as well. Could even start simply with a disk formatted with US Doubler Ultraspeed skew in SD card and ED. Then maybe Indus super syncromesh, and maybe other custom skews (would have to make custom USD formatter) like 3,2 and 1:1. Hopefully something better than those dismal RWTest results. I'm curious to know what sector skew it formats a disk with, and if it's different for side 2. (D2: writing backwards with track buffering?) Maybe the ROM dump alone would reveal it's format skew, if that feature was even implemented... Quote Link to comment Share on other sites More sharing options...
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