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Codes Demystified

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A bit confused reading the Designer Mode info the spreadsheets that Cheezmo and Stephen Smith have made available to Tosh folks?   Here's a bit of Offset 101.

Tip from Craig Rosenthal:  "While your set only has one user memory, it actually has a number of internal memory settings for different picture modes.

There are different internal settings for Normal and Theater modes, and for different signal types (composite video/svideo vs. component and 480i vs. 480p and 1080i signals).

The use of offsets allows a particular parameter to be defined for all modes (i.e., globally), or only for some specific modes (locally).   Rather than defining a new parameter independently of another parameter, an offset is a way to relate two parameters together, but to also allow independent values to apply to each. Essentially, you add the values together, and use the resulting value.

For example, all of Toshiba's contrast settings use CNTC to start (the global setting). If you are using the non-component video inputs (composite/S-video), then SCNT is added to the CNTC value to arrive at the contrast setting for these inputs.  IF, however, you are using the component input AND you are feeding a 480i signal the you add DDCT to the setting instead of SCNT.

So, if you want to change the contrast for all modes, change CNTC. If you want to change the composite video & svideo inputs only, change SCNT only; if you want to change 480i component video only, change DDCT.

Similarly EOCT is added if you are in Theater Mode, rather than in Normal Mode. This allows a different contrast setting to apply to Theater Mode. For example, you might want to set the contrast 10 ticks lower when in Theater Mode. Rather than have a separate setting to accomplish this for each input, EOCT applies to all inputs, but only when Theater Mode is selected.

Obviously, adding zero to any value leaves it unchanged. Adding 01, 02, 03, etc. increments the value by 1, 2, 3, respectively. Adding FF, FE, FD, etc. decreases the value by 1, 2, 3, etc. respectively (this is a way to subtract, rather than add). Note that all values are in hexadecimal notation - 00 is the minimum; FF is the maximum."

Stephen Smith's adds:

"I think the simple answer is: offsets allow the user controls to work on every input format with minimum memory requirements.

Toshiba defines a standard set of parameters and then adds various input format offsets only where needed. If each input format had it's own set of params, the list would be practically 12 times longer than it is now!

I think we should all thank Toshiba for the foresight to design such a flexible adjustment schema. I don't think any other manufacturers even come close to amount of adjustment flexability as we have here."