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From: brown@nicmad.UUCP
Newsgroups: net.micro.cbm
Subject: Re: EPYX Fast Load and "Edit Disk" function
Message-ID: <675@nicmad.UUCP>
Date: Thu, 1-May-86 12:30:15 EDT
Article-I.D.: nicmad.675
Posted: Thu May  1 12:30:15 1986
Date-Received: Sun, 4-May-86 03:41:11 EDT
References: <273@nbs-amrf.UUCP>
Reply-To: brown@nicmad.UUCP (Mr. Video)
Distribution: na
Organization: Nicolet Instrument Corp. Madison WI
Lines: 47

In article <273@nbs-amrf.UUCP> sauder@nbs-amrf.UUCP (Jeff Sauder) writes:
>Recently I downloaded a sequential file from a bulletin board, only
>to find that the file came across as a program file.  I realize
>there are utilities to change the type of a file, but being a true
>hacker, I decided that I must attempt to rectify the situation
>myself.  According to my 1541 reference manual, the location of the
>directory information resides on track 18.  However, when I
>attempted to use the "Edit Disk" function of my EPYX Fast Load
>cartridge to alter track 18, I found no information on track 18.
>(According to the "Edit Disk" function, anyway)  I eventualy
>located the correct information on track 12, altered the hex code
>so that the program file was now a sequential file, and then
>proceeded to use the sequential file for its desired purpose.  My
>question, however, is this --  What is wrong with this particular
>function on Fast Load?  I know that the information was really on
>track 18.  Are all track numbers actually referenced by a number
>six less than the true number (i.e. 12 instead of 18)?
>
>Also, I attempted to write directly to track 18 of the disk with
>limited success.  I tried to place the information '255' and '129'
>into track 18, sector 1, bytes 3 & 4 respectively.  (129 is the
>code for sequential files while 130 is the code for program files.
>I was trying to replace 130 with 129 and I assumed that I also had
>to write the previous 255 to the disk also, because I could find no
>way of skipping over a byte within a sector.)  Anyway, I
>accomplished the desired feat with undesirable side effects.  My
>short little program continued writing '255' and '129' throughout
>the entire sector.  All the odd numbered bytes had '255' in them
>and all the even numbered bytes had '129' in them.  Is it possible
>to write to only part of a sector, or must I write to the entire
>sector when attempting a Block-Write?  
>
>You can send me E-mail if you wish, but I'm willing to bet that
>some others may be interested in this, too.  Thanks in advance.

I too have said Fastload cartridge.  Your simple mistake is that you
are taking the decimal track number and applying it to Fastload.
It wants HEX track and sector numbers.  So, you should have entered:
	track  12	sector 01
Then it would have worked (and does work).
-- 

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