apple2_printm/README.md

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#printm - a modular micro printf replacement for 65C02
Here is a *modular* _micro_ replacement: printm()
* Literals have the high byte set (APPLE text)
* Meta characters have the high bit cleared (ASCII)
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```
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$ Hex - print 2 Byte
x Hex - print 4 Byte
@ Ptr - print hex byte at 16-bit pointer
& Ptr - print hex word at 16-bit pointer
# Dec - Print 1 Byte in decimal (max 2 digits)
d Dec - Print 2 Byte in decimal (max 3 digits)
u Dec - Print 2 Byte in decimal (max 5 digits)
b Dec - Print signed byte in decimal
% Bin - Print 8 bits
? Bin - Print 8 bits but 1's in inverse
o Oct - Print 1 Byte in octal (max 3 digits)
O Oct - Print 2 Byte in octal (max 6 digits)
a Str - APPLE text (high bit set), last char is ASCII
s Str - C string, zero terminated
p Str - Pascal string, first character is string length
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```
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Each option can individually be enabled / disabled
to control the memory footprint since you probably
don't need "every" feature. Seriously, when was the last time
you _needed_ octal? :-)
printm() has manually been optimized for size. In gcc parlance, `-Os`.
With everything enabled printm() takes up less then 512 bytes.
See the latest code for the exact byte usage!
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* By: Michael Pohoreski
* Copyleft {c} Feb, 2016
Special Thanks:
* Sheldon for his 65C02 printf() source
* qkumba optimizations
Join the discussion in comp.sys.apple2.programmer
* https://groups.google.com/forum/#!topic/comp.sys.apple2.programmer/cXqTp7YLYuo
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