Seems that it was just a bad mastered disk. There are original disks working correctly. The correct working disks has the track 20 unformatted. The non working one has track 34 unformatted instead.
Name of the game tells it like it is, or was : Magneto Bugs, bugs in magnetic media ... nevermind.
Adam Archambault - 16/06/2009
we owned this one but all got ruined in the shed. Please someone find this
|Other version with the same title: |
Main Street Publishing.
Re-release of Tumble Bugs.
Two files included.
"A" is the unmodified / original disk and does not load through. Actually, either due to a bug or an error during the duplication process, it appears no working original ever surfaced! For preservation purposes, we are keeping this VAPI image in the archive.
"B" is a fully functional, fixed version by Fandal with just a single byte to the code changed. Presumably, the original should have looked like this.
Below is Fandal's explanation...
"If your ATX image is a copy of an original disk, there never was any chance it could boot. There is a bug in the code.
I'm attaching a fixed version of ATX image. I changed just one byte as I noticed that there is a lot of bad sectors on original ATX starting at sector $265. Please note that loader checks sector $16D using this construction in the code:
18BE LDA #$6D ; LO byte of sector
18C0 STA $030A ;DAUX1 -> SIO table
18C3 LDA #$01 ; HI byte of sector
18C5 STA $030B ;DAUX2 -> SIO table
18C8 JSR $E453 ;DSKINV -> read sector
18CB LDA $0303 ;DSTATS -> read error flag
So I said to myself: may be it should check sector $26D instead of $16D? I changed LDA #$01 to LDA #$02 and voila! It works now.
I'm not sure if it is a programming bug or the master disk of Magneto Bugs
was damaged somehow but I would say that this mystery is solved".