DB> --------------- ;[BLINKY.ASM] - Public Domain by Denis
 DB> Boyles
 DB>        ;set ES to access BIOS data     xor     byte ptr
 DB> ES:[417h],LED      ;toggle LED via BIOS keyboard byte 
Gak! TAB's in your source code?  Anyhow, it is a prudent thing
to issue a call to int 16/1 after the change to the BDA. Some
BIOS' issue the call on every timer IRQ, some don't. Those that
don't won't change the LED and your program won't work.  :-)
--- timEd 1.01
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