jbm@uncle.UUCP (John B. Milton) (12/29/88)
In article <413@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes:
[describes merciless feet stomping and how he got the 2nd hard drive going]
I'm glad to see the schematic you got worked ok.
Yeah, yeah, I've been slackin' lately. My design is now complete except for
some board layout details. Now for the grubby details...
Unlike the P5.1 upgrade, this upgrade CAN NOT be passive.
Some wires just HAVE TO BE CUT FOR IT TO WORK!
For older mother boards:
13N-1 must be clipped loose and connected to grounded. 13N-2 must be clipped
loose and connected to 14M-3. This is actually an upgrade done by Convergent
on later mother boards.
For all mother boards:
13K-3 must be clipped loose from the board.
Parts list so far:
1 double sided PC board
1 26LS31 differential line driver
1 26LS32 differential line receiver
1 16R8 PAL
2 16 pin sockets
1 20 pin socket
4 20 pin headers
2 34 pin headers
3 bypass caps
4 100 ohm resistors
Other parts needed:
1 long 34 pin daisy chain cable with one header connector and at least two
drive connectors
1 an internal 34 pin cable to go from the mother board header to the header on
my board
? 20 pin data cables for each hard drive
1 external box and power supply
Connections inside the UNIXpc:
1. Data bus line D1
2. Data bus line D2
3. Data bus line D3
4. The register select line MCR2SEL*
5. volts.
6. The hard disk read data line to the hard disk data separator PAL, 14M-3
7. The hard disk write data line, 16M-6
8. Maybe the RST* line.
It will:
1. Add select lines for 3 more drives to the 34 pin cable. (total of 4 drives)
2. Provide a 34 pin header.
3. Provide active data connectors (20 pin) for 4 drives.
4. Work no matter how you mount it. (within reason)
5. Make you the envy of all your friends.
It will not:
1. Provide P5.1 board version feedback.
2. Provide additional 4th head select bit.
3. Provide floppy tape support.
4. Provide a watch dog circuit.
5. Force you to take out your fan if you don't want to.
6. Cost too much. A price of $50.00 is what I'm shooting for now.
7. Affect the price of tea in China.
Since the 3 drive selects have to be added to the 34 pin cable, the ground and
DDRIVE0* line will be picked off of the 34 pin cable from the mother board.
This will save two patch wires.
I am assuming that your machine will have the "P5.1 FIELD UPGRADE" already
installed. I will make that available as a SEPARATE kit. As I have mentioned
in the HwNotes, you do not HAVE to have the P5.1 to use two drives. You DO have
to have the P5.1 to format the second drive without swapping cables around.
I plan to have a patch for the diag disk (3.5 and 3.51) by the time I start
selling. The reason I am not providing the P5.1 on my board is that a lot of
people already have the P5.1 installed. I also wanted to keep the number of
wires going to my board down. The P5.1 part can be installed and tested
separately, thus easing the upgrade process.
I will be providing: the board, schematics, parts list, board layout,
background, theory of operation, patch wiring instructions, formatting
instructions, and probably a disk with HwNotes and other stuff. The text part
of the instructions will be posted for review.
Work is progressing on modifying the hard disk driver to USE all four hard
drives. It will not be available with the initial release of the board, but
will be posted in source form if and when I get it done. Until that is
available, you will be restricted to only two hard drives.
As far as the fan wars go, I have designed the board so that the cable headers
will match up with the fan grates. I will recommend in my instructions that
the fan be removed, the board be placed in that space, and that the existing
internal hard drive be mounted in the external enclosure with the second drive.
There will, of course be a melt down disclamer :)
As always, it's never too late to get your opinions and advice in on the
design of this board. If there are bugs found later, I would expect at least
50% of them fixable with a PAL change. Any of what I have described here may
change between now and when I get evrything working.
John
--
John Bly Milton IV, jbm@uncle.UUCP, n8emr!uncle!jbm@osu-cis.cis.ohio-state.edu
(614) h:294-4823, w:764-2933; Got any good 74LS503 circuits?gil@limbic.UUCP (Gil Kloepfer Jr.) (12/31/88)
In article <450@uncle.UUCP> jbm@uncle.UUCP (John B. Milton) writes: |>In article <413@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes: |>[describes merciless feet stomping and how he got the 2nd hard drive going] Awwww...c'mon John, put a smiley after that! |>I'm glad to see the schematic you got worked ok. Not without modification (those of you who may have "it"). Good thing I have the schematics for the machine itself, because there are some real gotchyas with what was printed. Mainly has to do with the output of the line receiver used for the first hard disk going to a couple of places. You have to know exactly WHAT pin to lift (and in some cases, what to move after you lift it). |>Yeah, yeah, I've been slackin' lately. My design is now complete except for |>some board layout details. Now for the grubby details... I had no doubt that this would be the case soon! |>There will, of course be a melt down disclamer :) Of course... I think an interesting addition to John's interface would be to PROVIDE the P5.1 upgrade along with the board. It would be interesting to see how many agree. A clarification (again) for the benefit of the net -- I was *not* trying to outdo what John is currently working on. His upgrade has much more (I can't wait) than the one I installed (I didn't design the upgrade either, it was due to John and a couple of others that got me where I am in the first place). Sorry for the long clarification. ------- Gil Kloepfer, Jr. U-Net: {decuac,boulder,talcott,sbcs}!icus!limbic!gil ICUS Software Systems Voice: (516) 968-6860 [H] (516) 746-2350 x219 [W] P.O. Box 1 Internet: gil@icus.islp.ny.us Islip Terrace, NY 11752 "Life's a ... well, you know..."
mkp@taqwa.UUCP (Michael K. Peterson) (01/01/89)
In article <417@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes: >I think an interesting addition to John's interface would be to PROVIDE the >P5.1 upgrade along with the board. It would be interesting to see how many >agree. I agree completely. I would prefer to do both upgrades at the same time. -- Mike Peterson Internet: mkp@hac2arpa.hac.com UUCP: mkp@hacgate.hac.com Home: ...!hacgate.hac.com!taqwa!mkp
ignatz@chinet.chi.il.us (Dave Ihnat) (01/02/89)
In article <10@taqwa.UUCP> mkp@taqwa.UUCP (Michael K. Peterson) writes: >In article <417@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes: > >>I think an interesting addition to John's interface would be to PROVIDE the >>P5.1 upgrade along with the board. It would be interesting to see how many >>agree. > >I agree completely. I would prefer to do both upgrades >at the same time. This only if they're two separate upgrades, and CAN be acquired simultaneously, but need not be. There are myriad reasons for keeping the upgrades separate, and virtually no good ones for doing them both on the same card/upgrade: 1) Existing upgraded units. A combined upgrade either would be unavailable to these units--and there are a lot of them--or require that two upgrades be maintained, which is an unnecessary pain for the provider. 2) Complexity. Keeping it a separate upgrade keeps the complexity down, guaranteeing both a more reliable upgrade, and a simpler installation. 3) Cost The cost of the combined upgrade will be greater than a single upgrade; this affects both those who already have the 5.1 upgrade, and those who want multiple drives but for some reason wouldn't care about the 5.1 features. 4) Aesthetics. Simply put, the two upgrades accomplish different purposes. Keep them discrete.
gil@limbic.UUCP (Gil Kloepfer Jr.) (01/03/89)
In article <7348@chinet.chi.il.us> ignatz@chinet.chi.il.us (Dave Ihnat) writes: [With regard to agreement that the HD upgrade and P5.1 upgrade be done in the same upgrade] >This only if they're two separate upgrades, and CAN be acquired simultaneously, >but need not be. There are myriad reasons for keeping the upgrades separate, >and virtually no good ones for doing them both on the same card/upgrade: There are **VERY** good ones for keeping them on the same upgrade. I will start with those, since they answer many of your reasons: 1. The *only* real thing that the P5.1 upgrade performs is the creation of the MCR2 register (physical I/O port) which is used for a 4th head select bit, the second hard drive select bit, and the signal to the OS that P5.1 is installed. 2. Because of (1), having two separate upgrades means extra circuitry to decode the address bits which ultimately define the same port. Highly unnecessary. 3. The simplicity of the second hard disk upgrade, minus a lifted pin (can be left out if you never use the second hard disk upgrade) is just as easy as the P5.1 upgrade. To bring up an even more elementary point, the only reason why you'd want to upgrade to P5.1 in the first place is for a 4th head select (for a big disk drive) and/or the 2nd drive select. You might as well kill two birds with one stone than to keep opening the machine and fiddling with upgrades. >1) Existing upgraded units. > A combined upgrade either would be unavailable to these units This doesn't make too much sense in my book. Are you talking about these public-domain (sort of ;-) upgrades or commercial ones? If the latter, don't worry about it...there won't be. >2) Complexity. > Keeping it a separate upgrade keeps the complexity down Although not entirely wrong, the addition of the circuitry for the second disk select isn't complex enough to make it separate from the P5.1/4th-head. Furthermore, it means that you have to consider which upgrade will provide the bit for P5.1. Then you will end up having to install both if you want to use the upgrade that doesn't do P5.1. I believe you need P5.1 in order to use the second hard disk select bit. >3) Cost > The cost of the combined upgrade will be greater than a single upgrade Minimally. The extra chips/sockets necessary for the second hard disk will cost another $5-$8, depending on source. As it currently sits, the P5.1 upgrade with 4th head select requires a PAL which is not necessarily available to most folks (I had someone do it for me as a favor). The combined upgrade I proposed (and mentioned the $50 price) was that at absolute maximum to save my own neck should it be more for someone else. I *know* it can be done for a lot less than $50, and even less for someone who has a good stock of chips available (I do a lot of tinkering as a hobby, and keep a lot of chips around). >4) Aesthetics. > Simply put, the two upgrades accomplish different purposes. Keep them > discrete. I already mentioned how it works at the beginning. The aesthetic problem is only in getting the wires from the cabinet. If you don't use the 2nd drive select, then you never plug the cable into the jack on the perfboard, it's as simple as that. In effect, you are getting more for your money, and doing less to your motherboard over a period of time. Inasfar as motherboard work goes -- I would feel a lot more comfortable messing with my motherboard ONCE and leaving it alone, rather than connecting wires to it TWICE and increasing the chance for costly damage. I appreciate your opinion, but I don't feel that it is as substantial as it appears on the outside. Again, the two upgrades are closely related, and they're almost meant to be done together. I already have someone who wants to work on a PAL design which will likely eliminate 4 TTL ICs and could fit right on the motherboard like the current P5.1/4th-head upgrade (although I would prefer to see the PAL on a separate piece of perfboard with the appropriate disk driver chips, like John probably does). BTW: The combined upgrade now is a total of 6 chips, and about thirty inter-chip connections [Vcc/GND included]. There are 14 connections to the motherboard, which includes the power supply for the chips. Seven of the motherboard connections are required for the P5.1/4th-head upgrade. Hope this helps to clarify things a little. ----- Gil Kloepfer, Jr. U-Net: {decuac,boulder,talcott,sbcs}!icus!limbic!gil ICUS Software Systems Voice: (516) 968-6860 [H] (516) 746-2350 x219 [W] P.O. Box 1 Internet: gil@icus.islp.ny.us Islip Terrace, NY 11752 "Life's a ... well, you know..."
lenny@icus.islp.ny.us (Lenny Tropiano) (01/04/89)
In article <420@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes: ... |> |>Furthermore, it means that you have to consider which upgrade will provide |>the bit for P5.1. Then you will end up having to install both if you |>want to use the upgrade that doesn't do P5.1. I believe you need P5.1 |>in order to use the second hard disk select bit. |> ... This is absolutely true. The kernel checks for the revision level of the motherboard at location "revlev". If your board doesn't show that it's a P5.1 board, then the code for the 2nd drive will never be executed. John Milton did some work early on by fooling the kernel into thinking it's running on a P5.1 board, by writing the correct value into "revlev" using the old "adb /unix /dev/kmem" method. This had some strange side effects if I remember correctly? (John, what have you found?) As Gil said, the P5.1 circuitry is minimal, and it does give the possibility of installing *large* hard drives in your system, provided you have the proper power supply to run them. You don't have to, but it does allow you. Just think, two Maxtor XT2190 (159MB) drives ... Hmmm... :-) Most importantly it saves opening the machine to do the upgrade for P5.1/4-head select down the road :-) ... ... Hungry for more space, Lenny -- Lenny Tropiano ICUS Software Systems [w] +1 (516) 582-5525 lenny@icus.islp.ny.us Telex; 154232428 ICUS [h] +1 (516) 968-8576 {talcott,decuac,boulder,hombre,pacbell,sbcs}!icus!lenny attmail!icus!lenny ICUS Software Systems -- PO Box 1; Islip Terrace, NY 11752
mark@jhereg.Jhereg.MN.ORG (Mark H. Colburn) (01/04/89)
In article <420@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes: >>[Dave Inhat's comments deleted. Sorry Dave... ] >There are **VERY** good ones for keeping them on the same upgrade. I will >start with those, since they answer many of your reasons: [ A number of reasons that the P5.1 upgrade should be on the board... ] And what about us poor fools that have already installed the P5.1 upgrade? I ultimately don't care how it all is packaged as long as you don't say that since I have the P5.1 upgrade that I can't use the new board to get more disk drives... I am sure that there are other people out there in the same boat, Dave, for instance. -- Mark H. Colburn "They didn't understand a different kind of NAPS International smack was needed, than the back of a hand, mark@jhereg.mn.org something else was always needed."
ignatz@chinet.chi.il.us (Dave Ihnat) (01/04/89)
In article <420@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes: > [My input] >There are **VERY** good ones for keeping them on the same upgrade. I will >start with those, since they answer many of your reasons: > > 1. The *only* real thing that the P5.1 upgrade performs > is the creation of the MCR2 register (physical I/O port) > which is used for a 4th head select bit, the second hard > drive select bit, and the signal to the OS that P5.1 is > installed. But, if somebody's ALREADY installed this upgrade--as I have--youre upgrade, unless you do some arm-waving to make it compatible, is unusable to me. And some hundreds--or thousands?--of other upgraded machines. And yes, I did the upgrade myself, from information released by Convergent... > 2. Because of (1), having two separate upgrades means extra > circuitry to decode the address bits which ultimately > define the same port. Highly unnecessary. Again, unless you consider the multiple-upgrade problem. Also, this extra circuitry is, I believe, very minimal... > 3. The simplicity of the second hard disk upgrade, minus > a lifted pin (can be left out if you never use the > second hard disk upgrade) is just as easy as the P5.1 > upgrade. Ok, how does that work with P5.1 upgraded units? >To bring up an even more elementary point, the only reason why you'd want to >upgrade to P5.1 in the first place is for a 4th head select (for a big >disk drive) and/or the 2nd drive select. You might as well kill two birds >with one stone than to keep opening the machine and fiddling with upgrades. It's already been done to the machine I'm worried about. Does your upgrade allow for such units? >>1) Existing upgraded units. >> A combined upgrade either would be unavailable to these units > >This doesn't make too much sense in my book. Are you talking about these >public-domain (sort of ;-) upgrades or commercial ones? If the latter, >don't worry about it...there won't be. Oh, come now. OF COURSE there won't be any commercial ones! And yes, as I've belabored up to now, the information for the larger disk upgrade has been available for quite some time, and I'm aware of many machines that are modified (successfully) to use this upgrade, including mine. Your comment here is a no-op; included for amusement, but sidesteps an important issue. >Furthermore, it means that you have to consider which upgrade will provide >the bit for P5.1. Then you will end up having to install both if you >want to use the upgrade that doesn't do P5.1. I believe you need P5.1 >in order to use the second hard disk select bit. Ok. You have to install both. The P5.1 upgrade was so easy I coached a guy through it who had to practice on solder technique first... >>3) Cost >> The cost of the combined upgrade will be greater than a single upgrade > >Minimally. The extra chips/sockets necessary for the second hard disk >will cost another $5-$8, depending on source. Yah, OK. This was, I believe, low on my list. (On the other hand, when I was in school, $8 would buy 5 pitchers and two spare beers...) >As it currently sits, the P5.1 upgrade with 4th head select requires a PAL >which is not necessarily available to most folks (I had someone do it for >me as a favor). The combined upgrade I proposed (and mentioned the $50 >price) was that at absolute maximum to save my own neck should it be more >for someone else. I *know* it can be done for a lot less than $50, and >even less for someone who has a good stock of chips available (I do a lot >of tinkering as a hobby, and keep a lot of chips around). Well, if they're a tinkerer and have a lot of chips, then a PAL isn't too hard, either. If they're not, then both are problems. Still, I think that the fact that so many P5.1 upgrades have been done makes consideration important... >I already mentioned how it works at the beginning. The aesthetic problem is >only in getting the wires from the cabinet. If you don't use the 2nd drive >select, then you never plug the cable into the jack on the perfboard, it's >as simple as that. In effect, you are getting more for your money, and >doing less to your motherboard over a period of time. No, I meant keeping upgrades separate. One has already been 'released'; keeping the two separate both isolates the purposes of the upgrade--larger disks, and more disks--and remains downward compatible. Some people may never be able to, nor care to, afford 80 Mb disks, but can get two 20 Mb drives free. >Inasfar as motherboard work goes -- I would feel a lot more comfortable >messing with my motherboard ONCE and leaving it alone, rather than connecting >wires to it TWICE and increasing the chance for costly damage. Alternate opinion--mess with it once, and if it then works, you know THAT work is reliable and functional when/if the next modification doesn't work. Or, you have test equipment for a motherboard when twice the number of chip and wiring mods go bad? >I appreciate your opinion, but I don't feel that it is as substantial as >it appears on the outside. Well, I really do. Especially as--as you may have guessed--I have one of those upgraded units which won't be able to use your upgrade... >Again, the two upgrades are closely related, >and they're almost meant to be done together. I already have someone >who wants to work on a PAL design which will likely eliminate 4 TTL ICs and >could fit right on the motherboard like the current P5.1/4th-head >upgrade Well, you just included a custom PAL anyway--how about one which works in place of the P5.1 upgrade, or serves the same needs as both? Yes, they're related, but I think that unless you answer the problem of already-upgraded units, you're gonna get bad PR for this upgrade, despite the (appreciated!) effort you're putting into it. >(although I would prefer to see the PAL on a separate piece of >perfboard with the appropriate disk driver chips, like John probably does). Why? There are empty pads on the motherboard for the P5.1 upgrade that work marvelously; what's wrong with using them, if you already have to pull the MB and solder on it? >BTW: The combined upgrade now is a total of 6 chips, and about >thirty inter-chip connections [Vcc/GND included]. There are 14 connections >to the motherboard, which includes the power supply for the chips. Seven >of the motherboard connections are required for the P5.1/4th-head upgrade. >Hope this helps to clarify things a little. Well, yes--but actually, it reinforces my feeling that two separate, less complicated upgrade steps are much preferable to one comprehensive, complicated upgrade. Many people applying this will be inexperienced with hardware hacking (as with one fellow I coached through the P5.1 upgrade), and it'll make their (or my) job easier to debug a two-step upgrade. -Dave Ihnat Analysts International Corp.
jbm@uncle.UUCP (John B. Milton) (01/05/89)
In article <7362@chinet.chi.il.us> ignatz@chinet.chi.il.us (Dave Ihnat) writes: >In article <420@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes: >> [My input] Thank you Dave, that about says it. There are a lot of us out here who have ALREADY gone the big drive (P5.1) route and are still running out of space. >> 2. Because of (1), having two separate upgrades means extra >> circuitry to decode the address bits which ultimately >> define the same port. Highly unnecessary. Nope. All the decoding is already done. The FULLY decoded MCR2SEL* line, previously unused would drive one clock input in your design, two in mine, no problem. The bits for the MCR2 port can be latched anywhere, not just in one place, as in Gil's design. This is done all over the UNIXpc. Gil's design could be modified to NOT provide the P5.1 just by not adding all the wires, so his idea would work for folks who already have the P5.1 installed. Lenny, When revlev is set to 2 (by detection of P5.1 OR tweeked): The sign on message changes from P3..P5 to P5.1 (not by tweek) The phone driver WILL execute a stub when 2400 baud is selected. The gd driver will access the second hard drive. If you want to run my board without the P5.1 (and use only <=8 head drives), all you have to do is: boot, run tiny program in /etc/rc (revlev tweek), mount 2nd drive. For the diag disk, you will have to apply a patch to let it access the 2nd drive for testing, formatting or bad block entry. >>To bring up an even more elementary point, the only reason why you'd want to >>upgrade to P5.1 in the first place is for a 4th head select (for a big >>disk drive) and/or the 2nd drive select. You might as well kill two birds >>with one stone than to keep opening the machine and fiddling with upgrades. I am assuming that if you want to add both upgrades, you WILL kill two birds with one stone. The first (P5.1) can be installed and tested with the machine laying spread eagle, then my board added. Of course, the machine CAN NOT be run for more than about 5-10 minutes open. >>Again, the two upgrades are closely related, >>and they're almost meant to be done together. Not almost, they ARE two of the four for the P6 machine that got shot down. >> I already have someone >>who wants to work on a PAL design which will likely eliminate 4 TTL ICs and >>could fit right on the motherboard like the current P5.1/4th-head >>upgrade One of the major reasons I'm going for a mounted PC versus a buried perf board is a solid place to connect drive cables. There are no less than 6 connectors on my board, 5 of which go outside the system. I have doubts about all these functions fitting in a 20 pin PAL. Since there are ONLY pre-powered 20 pin spares in the back left corner, this is a problem. There is NO way if you consider all four drive selects. I looked at doing a piggy back board first. There is no clearence to get straight up headers in there, so you have to use 90 degree headers, so you can only use the edges of the board, which makes the board huge if you have 2*34+4*20=148 pins=14.8 linear inches=4 x 4 board. I shudder to think about what would happen if those cables coming in from outside the machine were yanked out... >>(although I would prefer to see the PAL on a separate piece of >>perfboard with the appropriate disk driver chips, like John probably does). But not the connectors? >Why? There are empty pads on the motherboard for the P5.1 upgrade that work >marvelously; what's wrong with using them, if you already have to pull the MB >and solder on it? I can think of 6 reasons (layer 1, layer 2...) Now for some things I forgot to mention in HwNote10. Yes, I will be including all the PAL equation stuff (PALASM source, JEDEC file). It's looking like a PAL16RP4 is the right one, and I will need the RST* line. I remain confident in the lack of effect on tea prices. Stay tuned, keep those opinions coming. John -- John Bly Milton IV, jbm@uncle.UUCP, n8emr!uncle!jbm@osu-cis.cis.ohio-state.edu (614) h:294-4823, w:764-2933; Got any good 74LS503 circuits?