Newsgroups: comp.sys.amiga.hardware,amiga.crosspost
Path: utzoo!utgpu!cunews!micor!latour!mcr
From: mcr@Sandelman.OCUnix.on.ca (Michael Richardson)
Subject: Re: Too many partitions for 14.4k
Message-ID: <1991Jun15.223714.28874@Sandelman.OCUnix.on.ca>
Organization: Sandelman Software Works, Debugging Department, Ottawa, ON
References: <ba569s984.7653@sycom.UUCP>
Date: Sat, 15 Jun 1991 22:37:14 GMT

In article <ba569s984.7653@sycom.UUCP> ba569s984@sycom.UUCP (Bill Allen) writes:
>Too many HD partitions mean big trouble with modem speeds >9600.
>I have 3-4 HDs, with 2-3 partitions each.  The 6-12 partitions cause
>random characters to be dropped during text displays at >9600.
>Even off-line, "ATI5 modem --> terminal" displays, exhibit this
>problem.

  a) I assume that you have RTS and CTS handshaking enabled on the
Amiga, and on the modem (which sounds like an HST)

  b) You are not running any background tasks, like a cron.

>Needless to say, file transfers are nothing but errors/resends.

  If you are trying to use the internal serial port at >9600 baud,
good luck. It does not do RTS/CTS in hardware, requires one interrupt
per character, and has a character buffer (if you can it that)
  To do >9600 you need hardware handshaking (the means that the CTS
line is controlled by the shift register, not by the serial.device).
This means an ASDG, Checkpoint, or I guess a CA= board (I understand
that the CA= board will only guarantee a maximum of 9600 baud on all
ports, but that one might be able to go to higher baud rates if you
aren't using all the ports)
  I think the 6552's used on the PDIO boards support hardware flow
control in the chip, but I have no specs on those beasts (yet)

>John "JrComm" Radigan is convinced this problem is caused
>by the system needing to check each partition for "disk-change",
>like floppies.  Has anyone seen a tool (like NoClick for

  So? If your system hasn't got the time to do a couple of disk block
reads, you aren't going to be able to do any downloading with a
streaming protocol. (Zmodem, btw, can be told the size of the
receiver's buffer, and will wait after sending that many characters
for an ACK. Of course, few implementions actually support this.)

>Is a patch to Expansion:gvpscsi needed?
>Is:
>RM> gvpscsi                    14468 ----rwed 03-Aug-90 14:42:50
>RM> : v3.7 (17 Jul 1990) Ralph Babel
>RM>
>the very latest release?

  Is this a Series I or II? i.e. is it a DMA controller? If it uses
polled I/O (likely inside an IPL 7 loop), then no wonder you are
having problems.

>I notice it reports the PRIORITY of each partition as 0, but

  That refers to the BOOT priority. (what order the system looks for
places to boot from)

>Steve Tibbets "TaskX" shows every partition as PRIORITY 10.

  File system handlers run at a default TASK priority of 10. This is
so that a user task running at the default priority of 0 that won't
completely stop all disk activity if it is CPU bound. 
  You might try:

  1> ChangeTaskPri 15
  1> JrComm
  
  and see what happens.



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