[Coco] Four slot MPI project

Gene Heskett gheskett at shentel.net
Sun Jul 29 22:05:58 EDT 2018


On Sunday 29 July 2018 21:40:42 Walter Zambotti wrote:

> Or maybe modify RBF manager to include other disk formats that support
> larger drives.
>
Not unless we throw all the 6809 machines under the buses drivers and do 
a burnout. The 6309 CAN do 64 bit math, but the 6809 is stuck with 32.

And while its been a couple decades since I did the original conversion 
of RBF.mn to run a bit faster on the 6309, adding the additional bits 
for bigger disks is not a trivial task. Cluster sizes can go up by 
powers of 2 until you hit the 4GB mark, at which point you've no more 
bits left, and a 1 byte file takes up 256 256 byte "clusters". That 
particular block of code WAS in the original RBF.mn, but was removed by 
Kevin in his Christmas present RBF.mn. I'm of the opinion that he did 
that to hasten the end of os9 by limiting the maximum disk size to 131 
megabytes. But I figured out what that code did, put it back in and 
verified that it worked at cluster sizes up to 16 on my own 1GB drives. 
So now the drives can go on up to 4GB.

> The current OS-9 directly supports many disk formats!
>
> -----Original Message-----
> From: Coco [mailto:coco-bounces at maltedmedia.com] On Behalf Of Gene
> Heskett Sent: Monday, 30 July 2018 2:56 AM
> To: coco at maltedmedia.com
> Subject: Re: [Coco] Four slot MPI project
>
> On Tuesday 24 July 2018 15:36:01 Zippster wrote:
> > Hi Gene,
> >
> > > On Jul 24, 2018, at 12:55 PM, Gene Heskett <gheskett at shentel.net>
> > > wrote:
> > >
> > > Looks great Ed. Only comment is your beard, its way too black. :-)
> >
> > I’m working on it.  :)
> >
> > > Projected price yet?
> >
> > I’m not 100%, but it’s looking like $140 with the case and power
> > adapter.
> >
> > - Ed
>
> That, in todays market, doesn't sound too bad, I could be interested
> in one when its ready.
>
> Now, let me throw something else your way. Hard drives tend to be
> fickle, and while I have removed them in order to give the corner of
> the shell a tap with a soft hammer just to break the stiction and get
> them started, and they'll run as long as they aren't turned off for
> another extended period of time like mine have been for around 2 years
> because I had around $12k worth of water control work, involving
> jackhammers and such damaging dirt makers at work for several days,
> and TBT I haven't yet totally restored things.
>
> So, what we as a group, I hear figures from the man that we are over
> 500 strong just on this list.
>
> Solid state drives are seemingly in freefall WRT prices, I just bought
> 3 60GB's for my cnc machinery for less than 75 cents a gigabyte. A
> 60GB is sublime overkill for a coco as its out of math ability at 4GB.
>
> But we seriously need a sata interface, and to widen the market count,
> it should not be an adapter from scsi to sata, as that would limit it
> to use with the relatively few scsi interfaces about. It should plug
> directly into a multi-pack. And because the drives are huge in
> comparison to what the coco can address, how about a dip switch to set
> the offset such that it could mimic 50 or so 2GB drives. Or even a
> register that could be poked from the startup to set that offset for
> /s1, leaving /s0 available as the default boot drive, but all on one
> SSD.
>
> There would of course be a huge data speed differential, but reading
> and writing a single 512 byte block at a time should make that a never
> mind as long as the buffer in the controller can handle 500megs/second
> either direction. The ones I have put in service are making 300 to 700
> megs a second. Since the coco's max transfer is 11 second per
> megabyte, the apparent speed will not be seen, other than the lack of
> seeking time since the SSD's don't have any. This is what one of them,
> attached to a rock64 viaits usb-3 port, reports:
>
> gene at rock64:~$ sudo hdparm -Tt /dev/sda3 [sudo] password for gene:
>
> /dev/sda3:
>  Timing cached reads:   1592 MB in  2.00 seconds = 796.28 MB/sec
>  Timing buffered disk reads: 772 MB in  3.01 seconds = 256.80 MB/sec
>
> That, the coco's will never see. But since drive tech is moving hell
> bent to SSD's we could sure use a modern storage format.
>
> Here is another of them, but its on a usb-2 port, which kills its
> speed but is still magnitudes faster than the coco's:
>
> pi at picnc:~ $ sudo hdparm -Tt /dev/sda3
>
> /dev/sda3:
>  Timing cached reads:   952 MB in  2.00 seconds = 475.46 MB/sec
>  Timing buffered disk reads:  72 MB in  3.04 seconds =  23.66 MB/sec
>
> What say you about that?  We really do need a sata drive interface,
> preferably with 2 ports so we can do backups.
>
> --
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> Genes Web page <http://geneslinuxbox.net:6309/gene>
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco



-- 
Cheers, Gene Heskett
--
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>


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