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#xon/xoff

#: 22951 S4/TelecommunicationsForum unknown
    14-Jun-86 07:51:51
Sb: #22904-#xon/xoff
Fm: scott drysdale 72127,1510
To: Richard Webb 74005,1265

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whoah! that video card you're talking about just sits there and accepts CHARACERS; the amiga's display is memory mapped, bit mapped graphics – the software has to DRAW the characters, once for each bitplane (one bitplane for each bit of color – from 1 to 5 times). just to increase the fun, it draws characters using the blitter, which is kinda like a DMA controller that can work on bits within words instead of being limited to byte boundaries. the blitter is in great demand by such things as the disk drive, other graphics/display functions, and sound, so each task has to wait in line for the blitter. that's why character output to the display can seem so slow. in addition, the amount of work needed to set up the blitter to write a character is pretty large – so if you output just one character at a time (through the character display system calls) it has to perform that setup operation once for each character. if you were to display a 20 character string, it would go MUCH faster if you sent all 20 characters with the same output call instead of one at a time. –Scotty