HP71 HP-IL new old-bug

[J-F Garnier]

As Bob said in a recent post, it is worth to re-read old documentation.

I found a new HP71 HP-IL old-bug in the Titan File articles that I didn't know. It's a pretty serious bug since it can corrupt the first file of your disc when the directory gets full. I didn't remember this bug and I didn't find any other reference of it. I named it the "end-of-directory" bug.

I documented this bug in the HP-IL section of my HP-71B bug page.

I could be a nice challenge to explain this bug...

J-F

[rprosperi]

(07-08-2016 01:22 PM)J-F Garnier Wrote:  As Bob said in a recent post, it is worth to re-read old documentation.

I found a new HP71 HP-IL old-bug in the Titan File articles that I didn't know. It's a pretty serious bug since it can corrupt the first file of your disc when the directory gets full. I didn't remember this bug and I didn't find any other reference of it. I named it the "end-of-directory" bug.

I documented this bug in the HP-IL section of my HP-71B bug page.

I could be a nice challenge to explain this bug...

J-F

Yes, re-reading the Titan File articles was quite a re-education for me! I thought I recalled "most" of what I had read/learned about the 71B back in the day, but some quality time reading these old articles proved that was just not true, and was also quite educational (and fun). And I've gone back to them more than once since my initial read in the last year...

[Dave Frederickson]

Perhaps that's what happened here: http://www.hpmuseum.org/forum/thread-1958.html

[J-F Garnier]

(07-08-2016 11:18 PM)Dave Frederickson Wrote:  Perhaps that's what happened here: http://www.hpmuseum.org/forum/thread-1958.html

Yes, it's possible. This is the exact symptom: the end-of-directory marker (32 bytes 0xff) are written after the last catalog entry, in case the directory is full this marker overrides the first 32 bytes of the first file (it should not be written of cause when the directory is full, and this is the bug).
In the case of the INDXUK disc, the directory is not full, but the first file may have been corrupted before on a previous disc, then copied on this disc.

J-F