jimomura@lsuc.UUCP (02/27/87)
I just received my Disto Super Controller aaannnd, I wish I could say
everything about it is wonderful, but it isn't. A minor annoyance is that
you'll have to cut a notch in the drive side edgecard to fit the block that
Tandy now puts in the connectors for polarity protection. A more important
problem is that the WD-1773 chip doesn't seem to read/write single density.
I couldn't get it to read an OS-9 Standard Format disk. Does anybody know
of a chip replacement that will work which will give me back the single
density capabilities?
This makes 2 controllers which won't work with OS-9 Standard Format.
The FD-501 controller (the new short controller from the Shack) and the Disto.
Does anybody know if any of the other 2nd source controllers still handle
OS-9 Standard Format? The controllers that are available are the J & M
controllers and the Hard Drive Associates controllers. Are there any others?
Cheers! -- Jim O.bandy@amdcad.UUCP (Andy Beals) (03/11/87)
In article <1608@lsuc.UUCP> jimomura@lsuc.UUCP (Jim Omura) writes: >Tandy now puts in the connectors for polarity protection. A more important >problem is that the WD-1773 chip doesn't seem to read/write single density. The 1773 definitely does read/write single density. Your vendor probably doesn't program it correctly. :-( andy -- Andrew Scott Beals, {lll-crg,decwrl,allegra}!amdcad!bandy +1 408 749 3683
dml@loral.UUCP (03/11/87)
In article <15129@amdcad.UUCP> bandy@amdcad.UUCP (Andy Beals) writes: >In article <1608@lsuc.UUCP> jimomura@lsuc.UUCP (Jim Omura) writes: >>problem is that the WD-1773 chip doesn't seem to read/write single density. > >The 1773 definitely does read/write single density. Your vendor probably >doesn't program it correctly. :-( > andy The single/double density select on Radio Shack and J & M disk controllers is address $FF40, bit 5 ($20): 0 = single density, 1 = double density. Other manufacturers (Disto, etc.) probably do the same thing, but I can't be sure as I don't have a Disto controller. The Radio Shack BASIC disk routines, and the RS/Microware CCDisk in OS-9, are both hard-coded with this bit set to a 1 for double density. I have considered writing single-density support into the new disk driver that I'm working on, but it would be a lot of trouble (and code, on a memory-limited machine) for little return. In fact, when I asked for responses to "what features would YOU like to see", the few answers I got rated it of very low importance. If some determined hacker out there wants to add single-density support to my NewDisk driver, you have my blessing. I'll even send you a copy of the source (freely distributable, just give me credit for the parts you use). ------------------------------- Dave Lewis Loral Instrumentation San Diego hp-sdd --\ ihnp4 --\ sdcrdcf --\ bang --\ kontron -\ csndvax ---\ calmasd -->-->!crash --\ celerity --->------->!sdcsvax!sdcc3 --->--->!loral!dml (uucp) dcdwest ---/ gould9 --/ Always put your clothes and weapons where you can find them quickly in the dark. -------------------------------
jimomura@lsuc.UUCP (03/12/87)
In article <15129@amdcad.UUCP> bandy@amdcad.UUCP (Andy Beals) writes: >In article <1608@lsuc.UUCP> jimomura@lsuc.UUCP (Jim Omura) writes: >>Tandy now puts in the connectors for polarity protection. A more important >>problem is that the WD-1773 chip doesn't seem to read/write single density. >The 1773 definitely does read/write single density. Your vendor probably >doesn't program it correctly. :-( Thanks Andy. Yes, I found that out shortly after I posted the message. In fact, it seems to be a timing problem due to some TTY 74... chip or other. I'm still looking for a solution, but the solution doesn't seem to be easy to come by. There are currently 3 commonly used disk controllers that I know of that use the same WD-1773 controller chip. I now have 2 of them. I *think* that the Disto may be fixable via changing a 74LS04 variant chip, but I'm not sure about this. I checked the new Shack controller and it doesn't have that chip anywhere, so I think I'm dealing with two significantly different implimentations of this controller. As a matter of interest, the J & M controller also uses this chip, and I believe the Hard Disk Specialist (?) controller also uses this chip. I don't know about the HDS controller, but I've heard that the latest J & M controllers have the same inability to use single density. Has anyone heard anything about a fix for *any* of these controllers? Cheers!! -- Jim O. > andy >-- >Andrew Scott Beals, {lll-crg,decwrl,allegra}!amdcad!bandy +1 408 749 3683
neals@tekigm2.UUCP (03/14/87)
In article <1389@loral.UUCP> dml@loral.UUCP (Dave Lewis) writes: >In article <15129@amdcad.UUCP> bandy@amdcad.UUCP (Andy Beals) writes: >>In article <1608@lsuc.UUCP> jimomura@lsuc.UUCP (Jim Omura) writes: >>>problem is that the WD-1773 chip doesn't seem to read/write single density. >> >>The 1773 definitely does read/write single density. Your vendor probably >>doesn't program it correctly. :-( >> andy > > The single/double density select on Radio Shack and J & M disk controllers >is address $FF40, bit 5 ($20): 0 = single density, 1 = double density. Other >manufacturers (Disto, etc.) probably do the same thing, but I can't be sure >as I don't have a Disto controller. > > The Radio Shack BASIC disk routines, and the RS/Microware CCDisk in OS-9, >are both hard-coded with this bit set to a 1 for double density. I have >considered writing single-density support into the new disk driver that I'm >working on, but it would be a lot of trouble (and code, on a memory-limited >machine) for little return. Just thought I'd mention, before someone runs out and mod's Newdisk to clear bit 5 of $FF40 to do single density, that besides being the double density enable bit, it also enables the HALT circuitry. This is because a 6809 at 0.9MHz isn't fast enough to poll the status register and do data transfers within the 23.5usec worst case (minimum) cycle time for double density, but it is VERY close. You'll have to include the polling stuff in the read/write routines. I think a nice solution would be for Tandy to include an internal disk controller that uses DMA. I wouldn't mind too much if they ripped the COCO 2 compatibility stuff out of the GIME ;-). Now coming to you from tekigm2, Neal Sedell
dml@loral.UUCP (Dave Lewis) (03/16/87)
In article <1558@tekigm2.TEK.COM> neals@tekigm2.UUCP (Neal A. Sedell) writes: >In article <1389@loral.UUCP> dml@loral.UUCP (Dave Lewis) writes: >>In article <15129@amdcad.UUCP> bandy@amdcad.UUCP (Andy Beals) writes: >>>In article <1608@lsuc.UUCP> jimomura@lsuc.UUCP (Jim Omura) writes: >>>>problem is that the WD-1773 chip doesn't seem to read/write single density. >>>The 1773 definitely does read/write single density. Your vendor probably >>>doesn't program it correctly. :-( >>> andy >> The single/double density select on Radio Shack and J & M disk controllers >>is address $FF40, bit 5 ($20): 0 = single density, 1 = double density. Other >Just thought I'd mention, before someone runs out and mod's Newdisk to clear >bit 5 of $FF40 to do single density, that besides being the double density >enable bit, it also enables the HALT circuitry. This is because a 6809 at No, no, nicht, nein! The DRQ-HALT gate is $FF40, bit 7. Just for all you hackers out there, here's the breakdown on the disk hardware port at $FF40: Bit Function --- -------- 0 Drive select 0; 1 = drive 0 selected 1 Drive select 1; 1 = drive 1 selected 2 Drive select 2; 1 = drive 2 selected 3 Motor enable; 1 = drive motors on 4 Write precompensation; 1 = precomp on 5 Density select; 0 = single, 1 = double 6 Side select; 0 = side 0, 1 = side 1 (Radio Shack uses this one for drive select 3 by making strange cables) 7 DRQ-HALT enable; setting this bit to a 1 causes the inactive (high) state of the 1793's DRQ line to assert HALT to the 6809. The latch that this bit is stored in is cleared when the 1793 generates an NMI to the 6809 at the completion of a command. And while I'm at it, the 1793 itself is ORG'd at $FF48: $FF48 Command/status register $FF49 Track register $FF4A Sector register $FF4B Data register Ya finds these things out, writin' a disk driver....... In article <2270@tektools.TEK.COM> jonh@tektools.TEK.COM (Andy Davidson) writes: >I have a couple needs... Does anyone have device drivers/descriptors to run the >terminal t1 through the rs232 pak? (Maybe a new /t2 or something) It is frus- /T2 should do the job..you DO have a Multi-pak, right? Stick the RS-232 pack in slot 1, put T2 and ACIAPak in your bootfile, and either use XMode in your Startup file to set the baud rate to 1200 or change the descriptor itself when building your bootfile. You can't use /T1 because it passes its I/O through the RS232 module, which uses the CoCo bit-banger port on the back. >Also, since OS9 is sooo disk dependent, I'd like to speed up my drives. How >do I cause them to use the 6ms track seek rate? (I have the old TRS-80 Mini You send me $10, I send you a disk with a new driver, a bunch of new utilities, and installation instructions. (Strictly Commercial, that's me) Seriously, though, I've written replacements for the Radio Shack CCDisk, OS9Gen and Cobbler modules that not only allow you to change the step rate of each drive independently, they also allow you to use double-sided disks. There are also a number of other utilities, including rewritten Dir, Dump and Makdir commands, plus a few Microware didn't think of. The disk includes commented assembly source for all the programs, and some procedure files to simplify installation. ------------------------------- Dave Lewis 4417 Idaho apt 4 San Diego, CA 92116 -------------------------------
jimomura@lsuc.UUCP (03/17/87)
According to a press release Tandy has OS-9 Level II available for the CoCo3. Check your local stores and see if it shows up. I doubt if it'll solve my Single Density problem, but other interesting things may come to light. Cheers! -- Jim O.
neals@tekigm2.UUCP (03/24/87)
>>> The single/double density select on Radio Shack and J & M disk controllers >>>is address $FF40, bit 5 ($20): 0 = single density, 1 = double density. Other > >>Just thought I'd mention, before someone runs out and mod's Newdisk to clear >>bit 5 of $FF40 to do single density, that besides being the double density >>enable bit, it also enables the HALT circuitry. This is because a 6809 at > > No, no, nicht, nein! The DRQ-HALT gate is $FF40, bit 7. OK, OK, one more time. Yes, I was wrong about the HALT enable being bit 5, BUT bit 5 DOES enable the NMI output from the disk controller cartridge as well as enable double density. Therefore, if you turn off double density there's nothing that's going to break you out of the read/write loop. Of course at single density speed there's enough time to poll the status register in the loop. Thanks for keeping me honest, Dave. ------------------------------- Neal Sedell neals@tekigm2 -------------------------------