Error in MC68000 user's manual?

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Error in MC68000 user's manual?

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mhjacobson
Contributor I

Hello,

I have noticed what may be an error in the MC68000 user's manual (as posted at this URL on NXP's Web site).

In section 5, in figure 5-4 ("Word and Byte Read-Cycle Timing Diagram"), the bottom line shows time intervals labelled "READ", "WRITE", and "READ".  However, if I'm not mistaken, all three of those intervals are reads.  The first is a word read (both LDS and UDS asserted); the latter two are byte reads (only LDS and only UDS asserted, respectively).

Please let me know if I've misunderstood.

Thank you.

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mhjacobson
Contributor I

Here is an image of the figure in question.

fig5-4.png

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TomE
Specialist II

That's fairly obviously a cut-and-past bug from Figure 5.3. That has been edited to make Figure 5.4, but they forgot to change the last line where the "Write" label is.

Those manuals were brilliant. That one is the 9th edition, dated 1993 or 2006. Nothing like their later manuals...

https://community.nxp.com/t5/i-MX-Processors/i-MX53-i-MX6-Reference-Manual-Spelling-Problems/m-p/341...

Tom

 

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Bio_TICFSL
NXP TechSupport
NXP TechSupport

Good!

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