16-Oct-82 00:36:00,4615;000000000000 Date: 16 October 1982 02:36-EDT From: Frank J. Wancho Subject: 80 TRK Mod and "N" drives To: NORTHSTAR-USERS at MIT-MC, INFO-CPM at BRL I have followed the directions given below for the 80 track mod and all seems to work! --Frank -------------------- El Paso, Tx, 14-Oct-82 The following is a description on how to use full 80 track capabilities of disk drives like the TANDON TM 100-2 on a North Star CP/M system using North Star CP/M 2.2 Release 1.1.0. The modifications worked when I checked it out initially, but only constant use of the 80-track system will reveal any bugs. Therefore, I can assume no liabilities whatsoever, nor guarantee that the mod will work for your particular system in any way. If you are NOT using dual sided drives capable of stepping 40 tracks per side, or if you are NOT using North Star's CP/M rel. 1.1.0 QD, then it is time for you to hit Control-C, otherwise read on. The following steps will guide you through the modification: 1. Prepare a SYSGEN image of the system you are currently using and name it SYS70.COM. 2. Load SYS70.COM using A>DDT SYS70.COM. 3. With the "S" command in DDT make the following changes: -S2C05 2C05 22 27 <= change max front side track from 34 to 39 (decimal) 2C06 ?? . -S2C0B 2C0B 23 28 <= change max number of tracks/side from 35 to 40 (decimal) 2C0C ?? . -S3013 3013 A9 C2 <= change disk length (max CP/M sector) 3013 ?? . -^C A>SAVE 70 SYS80.COM 4. Execute the file SYS80.COM and put the modified system on drive A:, then cold-boot. Your CP/M is now set up to utilize all 80 tracks on a 48 TPI DSDD drive. Please note than NO conversion is needed to use all 160 Tracks on a 96 TPI drive (such as TM 100-4). 5. >>>>> IMPORTANT <<<<< You are now accessing uninitialized areas of a diskette. You will have to convert all your diskettes from 70- to 80 tracks! To do this, you will have to transfer the contents of one DSDD disk to two SSDD disks using the 70 TRACK SYSTEM, and then copy the files back to a freshly formatted disk using the 80 TRACK SYSTEM. While this may be somewhat confusing and quite time-consuming, I think it is worth doing, since you get an extra 50k per diskette for your efforts. The tradeoff is incompatibility of DSDD diskettes with others. To remedy that, either exchange only SS disks, or reformat them when necessary. To further test this modification, I will soon convert all disks on the B: drive of the El Paso RCPM to 80 tracks. Happy hacking! Oh, and many thanks to whoever enabled me to do this by providing me with some insight into the workings of the BIOS..... El Paso, Tx, 14-Oct-82 This file contains information on how to convert North Star's FORMAT.COM to format 80 track drives. As with NS80TRK.MOD, these modification are tested but can NOT BE GUARANTEED TO WORK FOR YOU! 1. Modification of FORMAT.COM (for N* CP/M 2.2 rel 1.1.0. ONLY!!!) for use with a modified CP/M BIOS which allows 80 track drives: This is the sequence of commands to do it: A>DDT FORMAT.COM .... -S1EB 01EB 45 4F <= change max track from 69 to 79 01EC ?? . -S72E 072E 37 38 <= change display so it says "... 80 tracks..." 072F ?? . -^C A>SAVE 9 FORMAT80.COM This completes the conversion. Note that FORMAT will still correctly format single-sided diskettes. 2. North Star has an undocumented feature in rel. 1.1.0. This feature is the so-called "Nine"-drives. That means that N* CP/M 2.2, rel 1.1.0. is able to control 96 TPI drives. I have not been able to check this out, but see no reason why it shouldn't work. You HAVE TO designate a 96 TPI drive as such and will not be able to use any other than a 96 TPI diskette on it. To do this, answer the DRIVE-question in CPMGEN with a "N" instead of "D" or "Q". (You can't fool the system - have to have a real 96 TPI dual sided drive!) In order to format a diskette in "N"-format, you have to modify FORMAT.COM. FORMAT.COM is already prepared to handle N-drives. It will even offer this function if you respond with "9" when asked for the disk format. However, it's internal workings require your response to be "N", which is normally rejected. To make it accept "N" instead of "9" and be able to format N-drives, use DDT to change byte 01F9H from 39H to 4EH. Then you'll be able to use FORMAT.COM with 96 TPI drives. Again, Happy hacking! 17-Oct-82 02:19:00,3449;000000000000 Date: 17 October 1982 04:19-EDT From: Greg Heise To: NORTHSTAR-USERS at MIT-MC More notes from North Star land... 1. There are three 74LS123s on the double density controller board. Two of them (5A and 1B) are used in the density detection circuitry. It turns out that some 123's aren't fast enuf for the circuit. In order to insure operation, these MUST be either: a straight TI, a National with a star after the date code, or a Signetics with an "A" suffix. If you're not having trouble now, it's probably not worth bothering, but if you start getting bizarre errors and disk-related system hangs, look here first. I first heard about this in March of '80, but since I am still seeing Horizons with this bug, I suspect every one will eventually fail. 2. There is a modification to Advantages to improve grounding ON THE AC LINE. N* suggests that it be done on ALL Advantages immediately. The mod requires a fix kit from N*. It's free. 3. N* has released their version of a solution to the HD18/parallel printer problem (it's in rel 1.1.0 of CP/M). I can upload if anyone cares. N* CP/M supports both the 5 meg and the 18 meg hard disk standard, but not both at the same time (someone asked). 4. There is a problem with certain Advantage monitor boards which have a slow-blowing capacitor. If this one goes, it chain reacts through the monitor board, giving you the classic mushroom cloud. To see if you have this problem, turn the screen control knob on the back of the ADV up full. If there is a bright vertical band about a third of the way from the left screen border, CALL N* AND HAVE THEM CHECK YOUR SERIAL NUMBER! Unfortunately, I don't have this field notice in front of me, so I can't tell you what range the serial numbers fall into. 5. N* has released a new rev of their applications software timesharing system. As near as I can tell, the only substantive change is that the spooler works now. 6. As some of you may know, the 1.1.0 release of CP/M supports the new double-track-density drives. If you have the new drives you have to change one byte in the FORMAT program to get 784K free space on one 5 inch drive. 7. Rumor has it that BSG (who wrote NorthWord) wrote NorthWord II but N* bounced it (3 times, yet!) so BSG got sick of trying to please Chuck Grant and decided to throw it out in the market themselves. So BSG has now given us "WordWizard." Some of us ancient ones may remember WordWizard as the name of a particular program that was put out by Processor Technology (makers of the Sol) before their confusing demise -- and yes, it's the same people: when N* first introduced NorthWord, I called it WordWizard to their faces and they changed the subject REAL FAST. The new incarnation of NorthWord/WordWizard/NorthWord II (call it what you will) runs only on Advantages, and has most of the limitations of NorthWord, but it spools, uses printers more intelligently, and makes very good use of the Advantage graphics. There is also a spreadsheet available now, and something called InfoManager II is obliquely referred to. I haven't used it, but here nevertheless I make An Opinion: don't bother -- accept the awful command set of The Final Word or (worse) WierdStar, and count your blessings. -- Greg 19-Oct-82 14:52:00,677;000000000000 Date: 19 Oct 1982 1652-EDT From: ELIOT at MIT-DMS (Eliot Scott Ramey) To: fjw at MIT-MC Cc: info-cpm at BRL, northstar-users at MIT-MC Subject: A better way to 80 tracks Message-id: <[MIT-DMS].246812> I passed Sigi Kluger's NS80TRK.MOD file on to Bob Plouffe. After looking at it he quickly saw a need for compatibility with 70 tracks. He therefore has a file that will easily enable one to patch his NS BIOS for handling BOTH 70 and 80 tracks. I will talk to Bob and see how he wants to go about getting it to MIT. (I still have to ask him about a bug I am encountering with ZCPR/NZCPR, so right now it works for standard CCP only) -Eliot at Mit-DM 19-Oct-82 18:47:00,571;000000000000 Date: 19 Oct 1982 2047-EDT From: ELIOT at MIT-DMS (Eliot Scott Ramey) To: fjw at MIT-MC Cc: northstar-users at MIT-MC, info-cpm at BRL Subject: Plouffe's 80 trk mod Message-id: <[MIT-DMS].246841> After pointing out my previously stated problem to RLP, he promptly found the error and now has his 80 trk mod set up so there is no dependence on CCP. I assume when he has completed it all, he will upload the file so all N* users can benefit from it. Remember, with this you don't have to have 2 copies of CPM, one for each config. -Eliot at Mit-DM