teletext solid block

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grobda
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teletext solid block

Post by grobda » Wed Feb 28, 2018 11:14 am

probably a simple thing but googling is getting me nowhere;

im trying to draw some graphics in mode 7 using teletext "sixels" but cannot seem to get a solid block. i've seen it referred to as 127 but this is 'backspace and delete' and does exactly that. the only two solid blocks i can see (32 and 160) both appear as solid background do you need to change the background colour and use one of these background blocks or is there a foreground solid block character i'm missing?

guesser
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Re: teletext solid block

Post by guesser » Wed Feb 28, 2018 12:16 pm

160 is just 32 with bit 7 set. That's the space character in alphanumeric mode and blank sixels in mosaic mode. character 127 is a block occupying the area of a character with no descender in alphanmeric mode, and all sixels set in mosaic mode. To print it from basic set bit 7 (i.e character 255)

A filled red block:

Code: Select all

PRINT CHR$(145)+CHR$(255)
A web based teletext editor which can export as Mode 7 screen memory: https://zxnet.co.uk/teletext/editor

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Rich Talbot-Watkins
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Re: teletext solid block

Post by Rich Talbot-Watkins » Wed Feb 28, 2018 12:20 pm

Try adding 128 to the ASCII code if you're writing it out with VDU or PRINT. If you're writing directly to the screen, 127 or 255 will work equally.

(As guesser just said :) )

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grobda
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Re: teletext solid block

Post by grobda » Wed Feb 28, 2018 12:59 pm

cheers 255 did the trick

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