Metrologic Optimus R, Руководство по программированию

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Chapter 2 Development Environment 15
2.4.7 Extended Reserved Words
These are the reserved words specific to this C compiler and all of them start with two
underscores ("_ _").
_ _adcel _ _cdcel _ _near _ _far
_ _tiny _ _asm _ _io
_ _XWA _ _XBC _ _XDE _ _XHL
_ _XIX _ _XIY _ _XIZ _ _XSP
_ _WA _ _BC _ _DE _ _HL
_ _IX _ _IY _ _IZ _ _W
_ _A _ _B _ _C _ _D
_ _E _ _H _ _L _ _SF
_ _ZF _ _VF _ _CF
_ _DMAS0 _ _DMAS1 _ _DMAS2 _ _DMAS3
_ _DMAD0 _ _DMAD1 _ _DMAD2 _ _DMAD3
_ _DMAC0 _ _DMAC1 _ _DMAC2 _ _DMAC3
_ _DMAM0 _ _DMAM1 _ _DMAM2 _ _DMAM3
_ _NSP _ _XNSP _ _INTNEST
2.4.8 Bit-Field Usage
The following types can be used as the bit field base types. The allocation is made as shown
in the illustrations.
Types Size in bits
char, unsigned char 8
short int, unsigned short int, int, unsigned int 16
long int, unsigned long int 32
The bit-field can be very useful in some cases. However, if memory is not a concern, it is
recommended not to use the bit-fields because the code size is downscaled at the cost of
degraded performance.