• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

quadra 630 owners - question re: serial port performance

Cory5412

Daring Pioneer of the Future
Staff member
If you already had an existing Quadra, it probably made a huge amount of sense to upgrade it, financially, even if it was going ot end up slower than a 6200 or slower than a particularly fast 7100 or 8100.

The cheapest of the x200 PPCs I can think of off hand is around $1900 for the Power Macintosh 5200/75LC, which was a pretty bare-bones configuration, basically meant to be sold to educational institutions that already had licensing for software. (So: not exactly a performa bundle.)

I'm sure there was either a performa variant or a 6200 variant for a little less -- possibly good if you were upgrading your own Mac and a 6200 fit the bill as a "letter writing and grolier's encyclopedia machine for the kids" when paired with, say, the old 13-inch color monitor from the IIci you would be shedding. Looking at MacWorlds/MacUsers from the era could be instructive on this, but I would bet that there was probably something around the $1,699 price point.

If you had a 475/605, you likely paid somewhere between $980 and $1,499 or so for it in 1993-1994. A 610 was $1449 in a pretty baseline config in 1993, so if a PPC upgrade card to get you to a 50-66MHz CPU was $500 you were saving a third of the cost of a new machine. On the other hand, depending on what you already had with, you weren't also getting the 15-inch multi-scan display, a modem or new printer, a new copy of ClarisWorks, the newest encyclopedia, and so on, so there's a possibility that people who really did want the performa bundle would do better waiting for that, specifically.

Plus, Internet connectivity even in 1995 basically consisted of dialing in, fetching the mail and the news out of a few AOL or eWorld channels you picked, then perusing it at your leisure offline. It wouldn't be until a few years later that this wasn't a viable Internet workflow, because really, this is what I did even on my iMac, in like 2002. I'd hop online, fetch my mail, and then hop offline and peruse it later when I had time. A lot of this is because at the time you didn't have more than a few megs of mail storage quota, so the possibility of your email inbox filling up was varyingly mildly to very real.

(As an aside: at around this time, maybe a year or two later in like 1996-1997, SyQuest had built a cheap version of one of its big cartridge storage systems for Windows PCs. It used the parallel port, so it was exceedingly slow, but it strikes me as the perfect place to do periodic backup and archiving of different datasets and it always seemed like a bummer to me that that particular system didn't come to Mac. Of course if you look up reviews and posts about it from the time, it was quite problematic, a lot more problematic than zip would be until a few years down the line when the zip click of death started happening.)

 

Cory5412

Daring Pioneer of the Future
Staff member
To bring it back to the whole MIDI question: Now that you've turned off AppleTalk, have you had a chance to try the 64XTC? There's a possibility that interface will also work now.

 

Cory5412

Daring Pioneer of the Future
Staff member
Have you had an opportunity to try out the other MIDI Interface? It would be interesting to find out if it now works properly with all the different software you want to use.

 

Cory5412

Daring Pioneer of the Future
Staff member
I had occasion to look at the 5200-6200 dev notes recently. There's nothing to indicate that it, being literally a 630 with a PPC upgrade integrated into the board, has different performance on that front than a Performa 630.
 
In fact, most of the totally weird utterly brain-dead things people write about regarding the 6200 are wrong because wel... being brain-dead, that's not what Apple actually did, or how the system is actually built.

Included in the article are discussions about how faster modems do in fact work and it appears to be generally accepted that they get faster with newer OS versions. The author has a 6300/100, but their 6300/100 is basically most of the speed of an 8100 or 7500 at a similar speed.

Anyway, if the 5200/75 board isn't good enough (it probably is), a /100 603e board will behave like a completely different system and is also a viable option.

The performance of a PPC-upgraded Performa 630 would still be really interesting to see. If that upgrade has more cache L1 instruction/data cache it could be a huge benefit over the slightly-too-small amount the 603s integrated into /75 603 systems.

Thinking about this a little further, my guess as to why MIDI wasn't working at first is because AppleTalk was likely trying to use the modem or printer port your MIDI adapter is on, but even if it wasn't that, AppleTalk has always been one of the biggest drains on Mac resources and is better to disable when you're doing compute heavy work or anything that needs to be almost-real-time, so it's not at all surprising that the machine behaves completely differently with it turned off.

Anyway have you had a chance to try the other adapter or any of the other software? That should all now work as well as the other configuration that was posted.

 

Cory5412

Daring Pioneer of the Future
Staff member
There was a small variety PowerPC upgrade cards compatible with the Performa 630. More details are here.

There's a possibility that some of these cards are faster than a 5200/75 or a 6200/75. It would seem like it would depend highly on the particular card you got (because some of them are pretty slow, especially if you install them in some of the 25MHz systems they support) and a detail not given on LEM's page: how much L1 cache they have. On the other hand, there are the 100MHz cards, and those, especially with the L2 cache, should outperform some early low end PPC machines like any 6100 or 7100 without L2.

 

Cory5412

Daring Pioneer of the Future
Staff member
Thinking about it: Since the 5200 is literally​ a Performa 630 but with an integrated PPC 603 upgrade, (note: those cards are 601s), any weakness a 603 based design has, a 601 upgrade card likely would as well. Basically regardless of which CPU you put on that architecture, the aged Performa 630 architecture, entirely unmodified, it still the Performa 630.

It would still be interesting to test, however.

 

supernova777

Well-known member
im not sure im following your train of thought here

the reason i was interested in changing the motherboard was to get a 68k powered mac that has color graphics

im not concerned with upgrading.. im downgrading to fill in gaps in my collection of macs so that i can run software from the early 1990s on a proper system 7 machine that has a 68k proccessor

alot of software was rewritten to include native powerpc instructions after the powerpc conversion began in 1995.

so basically ALL mac software prior to 1995 was 68k native instructions/code. 

i want to run 68k software on a 68k cpu powered mac with color graphics.

i was trying to find an older mac like an SE/30 but that would have been black and white.

shipping + handling + prices were really high to buy a macintosh II.

so this is what i figured out.

no offence; but dont you think if upgrading was what i was worried about id be on here talking about MDDs with overclocked cpus! :)

or PC hackintoshes or something

re: 64xtc it does NOT work with the performa 5200CD

as outlined above, this is believed to be because of a lack of speed ability in the serial communications or due to hardare handshaking  - either way it does not work

 
Last edited by a moderator:

Cory5412

Daring Pioneer of the Future
Staff member
When this thread started, you hadn't ever tried your MIDI software with AppleTalk turned off.

Then, you turned AppleTalk off, and suddenly your other MIDI adapter worked very well.

Given that the 5200 is literally a 630 board with a 603 CPU on it, (which means that it does have hardware handshaking in its serial ports, which isn't used in MIDI anyway, but) then there's no reason this other MIDI adapter shouldn't work.

The 5200 literally does not have the hardware problems you're describing, so I believe something else is wrong.

---

At the end of the day, other than that the PPC is generally faster (and a 5200/75 really isn't an exception unless you're using old 68k-only software and you have an 840av as your 68k...), it doesn't make sense to change a 5200 using a 630 board, since you're not even building a model that ever existed. Most of the faster PPC systems (even something like a 5300/100) run 68k code faster than 68ks ever did, so if there's anything performance sensitive, buying a newer system is an easy way to speed it up.

If you want a 630, get a 630 and buy a monitor for it. Otherwise, there are a lot of 68k Macs to choose from. You're on a forum literally dedicated to them, so it might be worth checking out.

 

supernova777

Well-known member
"When this thread started, you hadn't ever tried your MIDI software with AppleTalk turned off."

im sorry you must have misunderstood

at no time did i say i had never tried with appletalk enabled

i made a statement where i logically included that as a possibility as to what was causing the midi interface to not work properly

here is the direct link to the message i left :https://68kmla.org/forums/index.php?/topic/30897-quadra-630-owners-question-re-serial-port-performance/?p=336302

heres a quote of the only time i mentioned appletalk: "im not sure if serial handshaking was totally not possible at all.. or if it was not possible with APPLETALK enabled.. or if it was not possible with a certain speed link (1Mhz required by multiport MIDI Interfaces such as the MIDI Timepiece or Opcode Studio interface series)"

i dropped a link to an article on midi timing: http://www.oldschooldaw.com/forums/index.php?topic=3361.0

i also dropped a link to an article on serial throughput: http://lowendmac.com/1998/macintosh-serial-throughput/

at this time i do not beleive my problems are/were being caused by appletalk being enabled.

at this time i believe that the midi ports on the performa5200CD are not functionally able to operate at high speeds necessary to use advanced midi interfaces with timecoding functionality such as the Opcode 64 XTC,

i have another older MIDI interface that is connected to the performa 5200CD right now, its the opcode Studio 3 (1989) - while it seems to work it still also does not behave 100% properly on the performa 5200CD. 

this topic needs to be finalized with some tests with the quadra 630 (powered by 68k cpu) and the same two midi interfaces.. which i will do once i get my hands on a quadra 630 motherboard to swap in.

i appreciate that you are trying to help + offer your expertise but unfortunately i think we are on somewhat of a different angle/wavelength here.

your comments clearly indicate that you  did not take the time to properly read + take in the information from the articles that i linked and presented here.

had you read them (or even just hte first article: http://www.oldschooldaw.com/forums/index.php?topic=3361.0)more clearly you would be familiar with the concept presented in the article that MIDI performance on the macintosh platform suffered small measurable delays resulting from the old original 68k code having to be processed/translated by the PPC processor ...

i suggest you re-read that article for you to get a handle on where im coming from!! im looking for the best MIDI timing performance possible, and based on the information presented in the article, that means having a 68k processor macintosh running native 68k software. 

theres a reason the ATARI ST is still toted as the fastest MIDI computer, but the original MAC 68k machines also were around in the same days of the ATARI ST.

MIDI Performance back in the early days from 1984 through to around 1990 was dominated by the ATARI ST running Steinberg PRO24 sequencer + the original compact macs running performer sequencer.

Performer was later rewritten to native power-pc code after 1995. such is the case for alot of other software packages aswell, they all attempted to achieve 100% native powerpc code once it was clear that the 68k processor was gone for good.

even if the new PPC processor was was faster;

in the timeframe of 1990-1995 (early 90s) 68k processor systems still reigned supreme for MIDI sequencing + audio processing

because all of the pre-existing software of the time was properl coded using native 68k code.

read the article!

it is interesting + intriguing.. 

if u are challenging that the article is false, thats your deal.

im not debating that, im exploring the possibility that its true.

 
Last edited by a moderator:

Cory5412

Daring Pioneer of the Future
Staff member
One more thought: Does your 5200 have an internal modem installed? If so, try removing it. I continue hearing reports that the modem even being installed in the system causes some of the performance problems.

Otherwise, I don't know what to say. The 5200's serial ports are the same as the 630. This LEM article you linked says every Mac since the plus supports hardware handshaking, but MIDI itself doesn't use it, but I don't know if a more involved MIDI interface may be using it. If so, lack of hardware handshaking isn't what's causing those problems.

Regarding 68k emulation: This is one of the reasons a common suggestion is to run the newest reasonable possible version of Mac OS on any given machine. System 8.0/8.1 should be faster than 7.6.1, and 8.5 or 8.6 should be faster than that, because those versions migrate away from 68k code.

Another thing to look into on 7.5 and 7.6 (and maybe 8, I haven't looked) is Speed Doubler, available here. The main feature of Speed Doubler is that it replaces the 68k emulation component with a more efficient one.

i suggest you re-read that article for you to get a handle on where im coming from!! im looking for the best MIDI timing performance possible, and based on the information presented in the article, that means having a 68k processor macintosh running native 68k software. 
The Performa 630 motherboard isn't what you want then, because it has the same serial system as the 5200.

Get a nice II-series machine or an LC series or a Quadra 700/610/650/800.

Honestly, it sounds like given everything you have written here and in your article on your other site that what you really want is an Atari ST. If so, perhaps it's time to hunt for one of those.

MIDI was a specific goal Atari had, so the system itself had  MIDI ports and the architecture was designed around making MIDI work well.

On the Mac, the use for serial was always for pretty generic peripherals which were presumed to be able to handle non-real-time operation. AKA, buffering a document to a printer one line at a time, or a slow local area network interface, and the Mac was also optimized for cost over all else. (Probably a little ironic to write, given that the ST cost less than a Mac, but.)

As one more note: I wouldn't at all be surprised if, as with all LEM articles pertaining to the 6200, these MIDI articles are basically untrue, based on hearsay and incomplete troubleshooting -- somebody couldn't get something working well enough, so they literally invented a possible reason as to why it didn't work. (Again, "Left 32" and "Right 32" as a great example of this.)

So, it's clear that you know what hardware will give you the best results. It even sounds like you actually know the 630, which its 660/840/5200-like geoports isn't it, so my recommendation is that if you want to continue with a Mac at all, and you absolutely must have a 68k Mac -- just buy one.

 

supernova777

Well-known member
no theres no mac driver exntesion for the 64xtc

the driver itself is called OMS and has built in support for the interface and it works fine on other macs i have

the ports on the 5200CD cant handle the higher speeds of serial communication 

thats why it cant handle modems faster than a certain speed

The 5200's serial ports are the same as the 630.
what ive read written by hinton instruments 

https://web.archive.org/web/20020408215342/http://www.hinton.demon.co.uk/mac/macmidi.html

leads me to believe otherwise. i guess well find out when i get a quadra 630.

also; the macos9lives driver page u linked is writen by me;) check the user name

 
Last edited by a moderator:

Cory5412

Daring Pioneer of the Future
Staff member
the ports on the 5200CD cant handle the higher speeds of serial communication 

thats why it cant handle modems faster than a certain speed

But, it has been proven that 5200s can actually use faster modems. Much of the early LEM (like 1997) talk centered around using any modem faster than 9600bps, but there are definitely people using 28.8 and 33.6 serial modems with them. There's no good reason you couldn't connect a 56k modem to one and use it at whatever the max speed your phone line can run.

If you look at the dev notes for the 630 and the 5200/6200, you will see that their architectures are the same and they have the same serial components.

I don't think that the emulation of 68k code is going to have near the impact you've said it will, but it could be worth putting 8.1 or 8.6 on the machine and using a PPC native version of the software you want to see if that works.

The other thing that's worth noting on this article you linked is that the problems it describes appear to mostly be related to people using serial port multiplexers/multipliers. Nothing on this page is specific to the 5200. The implication here is that if you were, say, the owner of a PowerMac 8100 or 7200 (at any speed) and had MIDI, a modem, a localtalk network, a printer, a newton, and a quicktake, you were going to run into the same problem. The problem here being that people have too many things connected to their serial ports.

The article doesn't really say that MIDI should be a problem on a system where it's the only thing you're doing, just that if you're doing a lot of different things, their PCI card is beneficial.

The page does little to discuss why you might use that card if you don't have a large number of serial devices connected.

One other interesting thing is that the technote linked shows that Apple ultimately replaced the serial driver with one that has native powerpc performance, again, on systems that use that particular chip, which it just lists as the 660 through the 8100, it doesn't exhaustively list models, so we don't really know if this applies to the 5200-6200 at all. All you have to do is make sure you're using the newer drive. The article about it was published in 1996 so I'm guessing the solution there is to install 7.6.1 or better.

also; the macos9lives driver page u linked is writen by me;) check the user name
I found some amount of humor in that. I'm glad you appear to have as well.

 

supernova777

Well-known member
Cory: i have tried system 8.1 on the performa5200CD for the reason of powerpc navtive code i did read abut that!

but upgrading is not what im looking to do ! you keep suggesting upgrades! the whole point in me getting a 68k mac is to go BACKWARDS in TIME to achieve compatibility with earlier versions of software that im interested in researching and experiencing / revisiting to be able to have a system that works with software from the late 80s + early 90s

the ultimate macs for me for this purpose would probably be an SE/30 or a Macintosh IIFX, or IIci, but like i said in my original post somewhere, those machines were not for sale at the time when i grabbed this performa (for 20$! lol!!! basically free) anyway im pretty happy to even figure out that i can turn it into a color 68k mac. i did get a network card and it is online and its downloading files from AFP fileserver that i have running NAS4FREE which works fantastically. 

re: " problems it describes appear to mostly be related to people using serial port multiplexers/multipliers." it means multi-port midi interfaces, such as the motu miditimepiece or opcode studio 4, multi midi port interfaces with more than 1x1 or 2x2 or 1x3 midi port configurations, which were the max for sometime, the limit/barrier was broken by upping the speed of the link to higher than 1Mhz i guess it gets problematic as the serial comm speed gets cranked up..  the ports could be set to different speed modes..... 

 

supernova777

Well-known member
cory: your comment about the technote brought me back to the serial DMA driver

how can i check to see if im running v8 or v9 of the serialDMA driver? because it says right there that they corrected the mistake with the next version:

https://www.fenestrated.net/mac/mirrors/Apple%20Technotes%20(As%20of%202002)/tn/tn1018.html

About the SerialDMA DriverThe SerialDMA driver which shipped in the system software of each DMA-capable Macintosh from the Macintosh Centris 660av through the Power Macintosh 8100/110 (1993-1994) was Apple's first-generation DMA serial driver. This driver was cursed by some architectural flaws. The flaws exhibited themselves primarily as latency problems, which affected software handshaking and certain kinds of read-write operation.

The original version of SerialDMA is identifiable as Serial Driver version 8. As Apple and several third-parties have discovered, version 8 may simply be unsuitable for some categories of applications.

In response, Apple is now providing a second-generation SerialDMA driver (version 9), which corrects the design flaws in the first version, increases compatibility with the classic serial driver to the greatest extent possible, and optimizes performance to realize the full potential of the available DMA hardware. The effects of this re-architecture include:

  • a much smaller driver footprint (over 30% smaller) in memory for the 68K version
  • native performance in the PowerPC version
  • significantly higher reliablility
  • better potential throughput, and
  • minimal latency in response to read requests and XOn/XOff handshaking characters.
 
Last edited by a moderator:

Cory5412

Daring Pioneer of the Future
Staff member
8.1 should have the v9 driver. I don't believe you can get the drivers separately, so it's a matter of figuring out what versions of the OS had it.

My guess is that 7.6.1 is your best bet if you want to have the v9 driver and also system 7.

The way the page about MIDI timing read was that the problem was basically that serial port capacity is limited by multiplexers. The way I read it wasn't about issues pertaining to adapters that have multiple MIDI i/o channels, as much as it is about somebody who has a printer, MIDI adapter, and Newton or Palm Pilot all connected to one port, while a modem and perhaps one or two more things are on the modem port.

Both of those things together would compound the problem that RS-422 serial isn't a very fast interconnect to begin with and that there are only two connections on Macs.

 

supernova777

Well-known member
http://download.cnet.com/Apple-SerialDMA-Update/3000-2072_4-421.html

this might be it - its posted back in 1998

 Description+
From Apple: Includes version 2.1 of the SerialDMA extension, which supplies a replacement serial driver for a specific set of Mac OS computers. This new driver fixes an incompatability that prevents certain serial devices, such as digital cameras, from establishing an initial connection. If you are using one of the Mac OS computers listed above, and you are using a serial device which cannot establish an initial connection, you should install this update
 
Publisher Apple Publisher web site http://www.apple.com/ Release Date July 09, 1998 Date Added July 09, 1998 Version 2.1
Operating Systems Mac/OS Classic Additional Requirements SerialDMA 2.1 extension works with U.S. English Mac OS 7.6.1, 8.0, or 8.1, and any of the following Mac OS computers: Power Macintosh 4400, Power Macintosh 5500, Power Macintosh 6500, Twentieth Aniversary Macintosh, Power Macintosh 7220, Power Macintosh G3, PowerBook 2400, PowerBook 3400, PowerBook G3, or PowerBook G3 Series. Download Information File Size 417.97KB File Name External File
 

 
Last edited by a moderator:

supernova777

Well-known member
the version numbers dont line up tho and it doesnt mention the performa 5200CD only mentions the performa 5500.

i think this might be an update TO THE UPDATE that im looking for

 
Top