gilf@VMS.HUJI.AC.IL (GIL FREUND) (05/31/91)
Hi All, I have been having problems working with a Perstor ARLL. This controller doubles the capacity of some MFM disk drives, and even speeds them up a little. However, since I installed this controller, DESQview hang, in almost every session, and communications are interupted. The dealer I baught the controller from refuses to acknowlage the problem, puting is down to the software (what else). I have heard elsewhere the Prestor and Zmodem conflict, and that Perstor is sending a fix for it, but my mail to Perstor was returned stamped "Service Discontinued". Does anyone else have any information? I think the problem is that the Perstor controller 1) uses memory locations that conflict with DESQview, and, 2) uses an interupt that conflicts with communication. Does anyone have any idea if those problems can be resolved using software alone? Can anyone send me the address for Perstor (the one on the manual is either wrong, or outdated)? Thanks in advance. Gil
geoffw@xenitec.on.ca (Geoffrey Welsh) (06/02/91)
(BTW, thanks for the note on LOADHI's /GS parameter!) In article <31MAY91094739@vms.huji.ac.il> gilf@vms.huji.ac.il writes: >However, since I installed this controller, DESQview hang, in almost >every session, and communications are interupted. The dealer I baught >the controller from refuses to acknowlage the problem, puting is down >to the software (what else). No, the fault lies almost exclusively in the Perstor's firmware. >Does anyone else have any information? I think the problem is that the >Perstor controller 1) uses memory locations that conflict with DESQview, I doubt it; I don't know why your machine is hanging, but losing characters on serial I/O is a common problem with those Perstor controllers, even without DesqView. The normal solution is to invest in an NS16550AF chip, which will give the CPU much longer to fetch the incoming characters. >and, 2) uses an interupt that conflicts with communication. As far as I know, there is no interrupt conflict, but the Perstor card either masks the interrupts or engages in very long DMA bursts, either of which will prevent the CPU from reading the incoming characters before they are lost. >Does anyone have any idea if those problems can be resolved using software >alone? Can anyone send me the address for Perstor (the one on the manual >is either wrong, or outdated)? As I said, I don't know if there's a quick solution to your machine hanging, but a 16550 will go far to help your serial I/O problems. Geoff
jayh@ms.uky.edu (Jay Hofacker) (06/03/91)
gilf@VMS.HUJI.AC.IL (GIL FREUND) writes: >I have been having problems working with a Perstor ARLL. This controller >doubles the capacity of some MFM disk drives, and even speeds them up >a little. >However, since I installed this controller, DESQview hang, in almost >every session, and communications are interupted. The dealer I baught >the controller from refuses to acknowlage the problem, puting is down >to the software (what else). I have no problems running my PS180-16FN 16 bit Perstor card in my BBS machine, which runs Maximus BBS software under Desqview 2.31 and QEMM 5.11. When I first installed the Perstor card, I did have problems with lock ups under DV, but I traced the problems to HyperDisk, a disk cache. The system locked up under DV when I had HyperDisk doing 'stagged writes', which means it caches writes to the drive as well as reads. After I set Hyperdisk to be a read-only cache (just like Microsoft's smartdrv.sys), the problem went away. -- Jay Hofacker, sysop of the Audio/Visual Exchange, (606)254-1751 3/12/24 MNP 5 Mail: jayh@ms.uky.edu / uk02779@ukpr.uky.edu -- Yes, my signature is only 2 lin
mlord@bwdls58.bnr.ca (Mark Lord) (06/04/91)
In article <31MAY91094739@vms.huji.ac.il> gilf@vms.huji.ac.il writes:
<Hi All,
<
<I have been having problems working with a Perstor ARLL.
...
<However, since I installed this controller, DESQview hang, in almost
<every session, and communications are interupted. The dealer I baught
<the controller from refuses to acknowlage the problem, puting is down
<to the software (what else).
<I have heard elsewhere the Prestor and Zmodem conflict, and that Perstor
<is sending a fix for it, but my mail to Perstor was returned stamped
<"Service Discontinued".
<Does anyone else have any information? I think the problem is that the
<Perstor controller 1) uses memory locations that conflict with DESQview,
<and, 2) uses an interupt that conflicts with communication.
<Does anyone have any idea if those problems can be resolved using software
Bizarre.. I have a 16-bit Perstor ARLL in my system, with two floppy drives,
two different hard drives, and a tape drive hung off of it. Desqview is my
primary operating environment. Never a problem. And ZMODEM (DSZ) is almost
always in use in a background window, at 9600bps.
There are a couple of possibilities here, the most likely of which is:
- a disk caching program that buffers a whole track at a time.
Since the Perstor tracks are 31 sectors vs. the usual 17 (MFM),
this could result in a very long interrupt latency when the disk
cache program uses EXTended memory: all EXTended memory transfers
are performed with interrupts disabled.
The solution to this is to a) specify a smaller limit on maximum
number of sectors to "read-ahead" or a limit for number of sectors
per XMS transfer (XMS = EXTended memory manager). b) An even better
solution is to install a 16550AFN serial chip in place of whatever
you currently have for the serial port.. and use a comm program that
knows how to take advantage of the FIFO on this chip. This can improve
tolerance of longer interrupt latencies.
--
MLORD@BNR.CA Ottawa, Ontario *** Personal views only ***
begin 644 NOTSHARE.COM ; Free MS-DOS utility - use instead of SHARE.EXE
MZQ.0@/P/=`J`_!9T!2[_+H``L/_/+HX&+`"T2<TAO@,!OX0`N1(`C,B.P/.DS
<^K@A-<TAB1Z``(P&@@"ZA`"X(27-(?NZE@#-)P#-5
``
endmlord@bwdls58.bnr.ca (Mark Lord) (06/05/91)
In article <1991Jun2.173146.9926@ms.uky.edu> jayh@ms.uky.edu (Jay Hofacker) writes:
<I have no problems running my PS180-16FN 16 bit Perstor card in my BBS machine,
<which runs Maximus BBS software under Desqview 2.31 and QEMM 5.11. When I
<first installed the Perstor card, I did have problems with lock ups under DV,
<but I traced the problems to HyperDisk, a disk cache. The system locked up
<under DV when I had HyperDisk doing 'stagged writes', which means it caches
<writes to the drive as well as reads. After I set Hyperdisk to be a read-only
<cache (just like Microsoft's smartdrv.sys), the problem went away.
How interesting. And I thought it was just my system. I too cannot use
Hyperdisk Staged writes while inside Desqview, even though it works fine
outside and in windows3 etc.. and the HyperDisk docs claim that it should
work okay in Desqview. Hmm.. time to reverse engineer the Perstor BIOS
and see 'xactly what they're doing in them ROMs..
--
MLORD@BNR.CA Ottawa, Ontario *** Personal views only ***
begin 644 NOTSHARE.COM ; Free MS-DOS utility - use instead of SHARE.EXE
MZQ.0@/P/=`J`_!9T!2[_+H``L/_/+HX&+`"T2<TAO@,!OX0`N1(`C,B.P/.DS
<^K@A-<TAB1Z``(P&@@"ZA`"X(27-(?NZE@#-)P#-5
``
endgeoffw@xenitec.on.ca (Geoffrey Welsh) (06/06/91)
In article <7021@bwdls58.bnr.ca> mlord@bwdls58.bnr.ca (Mark Lord) writes: >How interesting. And I thought it was just my system. I too cannot use >Hyperdisk Staged writes while inside Desqview, Stranger still, HyperDisk works fine for me, even staged writes! >begin 644 NOTSHARE.COM ; Free MS-DOS utility - use instead of SHARE.EXE >MZQ.0@/P/=`J`_!9T!2[_+H``L/_/+HX&+`"T2<TAO@,!OX0`N1(`C,B.P/.DS ><^K@A-<TAB1Z``(P&@@"ZA`"X(27-(?NZE@#-)P#-5 >`` >end I disassembled that to see what it did... it looked to me as if you tried to make all calls to open or create files fail; I ran it, but was able to create files using ECHO . > testfile Did I miss something?
rdippold@cancun.qualcomm.com (Ron Dippold) (06/07/91)
In article <7021@bwdls58.bnr.ca> mlord@bwdls58.bnr.ca (Mark Lord) writes: >In article <1991Jun2.173146.9926@ms.uky.edu> jayh@ms.uky.edu (Jay Hofacker) writes: ><I have no problems running my PS180-16FN 16 bit Perstor card in my BBS machine, ><which runs Maximus BBS software under Desqview 2.31 and QEMM 5.11. When I ><first installed the Perstor card, I did have problems with lock ups under DV, ><but I traced the problems to HyperDisk, a disk cache. The system locked up ><under DV when I had HyperDisk doing 'stagged writes', which means it caches ><writes to the drive as well as reads. After I set Hyperdisk to be a read-only ><cache (just like Microsoft's smartdrv.sys), the problem went away. > >How interesting. And I thought it was just my system. I too cannot use >Hyperdisk Staged writes while inside Desqview, even though it works fine >outside and in windows3 etc.. and the HyperDisk docs claim that it should >work okay in Desqview. Hmm.. time to reverse engineer the Perstor BIOS >and see 'xactly what they're doing in them ROMs.. It must be the Perstor or your version of HyperDisk. HyperDisk 4.20 works perfectly well with DesqView with full functionality. -- Standard disclaimer applies, you legalistic hacks. | Ron Dippold