What do ?LOAD ERRORs with tapes actually mean?

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Jeff-20
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What do ?LOAD ERRORs with tapes actually mean?

Post by Jeff-20 »

I'm using a PRG to WAV program to put my files on tape. They seem to load fine, but every LOAD ends with a ?LOAD ERROR.

The program is fine. When it run, it seems to all be there. But the error is always there when loading is done. I

have a clue: I stitched four programs together in one wave file, and the last one is out of sync. The program loads, but as many of you know, i tend to attach my user defined characters to the end of the file. The characters are off by 2 bytes. They appear to be "pushed down" where the data that should be in, say, location 7168 is in 7170.

What could be causing this problem? What exactly is a LOAD ERROR detecting? Could this be a hardware problem with the tape deck? Or could it be faulty tapes? I tried with multiple tapes from the same pack. Results were always the same. Could it be an issue with the recording volume?
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srowe
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Re: What do ?LOAD ERRORs with tapes actually mean?

Post by srowe »

LOAD ERROR basically means a bit (other than end of file) is set in ST ($90/STATUS). For the tape device the possibilities are:
  • bit 7 end of tape
  • bit 5 checksum error
  • bit 4 read error
  • bit 3 long block
  • bit 2 short block
Knowing which one is set should help identify the cause.
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Jeff-20
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Re: What do ?LOAD ERRORs with tapes actually mean?

Post by Jeff-20 »

ST = 32
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srowe
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Re: What do ?LOAD ERRORs with tapes actually mean?

Post by srowe »

Jeff-20 wrote:ST = 32
So bit 5, checksum error. The checksum taken of the data does not match the byte from the header.
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Jeff-20
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Re: What do ?LOAD ERRORs with tapes actually mean?

Post by Jeff-20 »

srowe wrote:
Jeff-20 wrote:ST = 32
So bit 5, checksum error. The checksum taken of the data does not match the byte from the header.
Forgive my ignorance, but what could have caused that? Tape flaw? Drive flaw?
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srowe
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Re: What do ?LOAD ERRORs with tapes actually mean?

Post by srowe »

I would guess the problem is in the WAV file.
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Jeff-20
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Re: What do ?LOAD ERRORs with tapes actually mean?

Post by Jeff-20 »

You were right. Fixed it. Thanks!
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