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Adding a delay such as the 20ms one we have in AVR programmer's initialization routine is tricky without a word like TICKS. This implementation is highly inaccurate, but more accurate and reliable than a "ballpark" DO..LOOP...
10 lines
342 B
Plaintext
10 lines
342 B
Plaintext
( See comment in B321. TODO: test on real hardware. in qemu,
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the resulting delay is more than 10x too long. )
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CODE TICKS 1 chkPS, ( n=100us )
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SI DX MOVxx, ( protect IP )
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AX POPx, BX 100 MOVxI, BX MULx,
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CX DX MOVxx, ( high ) DX AX MOVxx, ( low )
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AX 0x8600 MOVxI, ( 86h, WAIT ) 0x15 INT,
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DX SI MOVxx, ( restore IP )
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;CODE
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