Page 39 - PIC18F4550微處理機C語言設計實務

૵ሔଡ଼ΥႧԊձ C ႧԊ 1

ҢࡁΎл͜ɓࡈഐ࿴ۨ࿒ၾ΍ۨ͜࿒ΥԻԴٙ͜ᇍԷdᜫᛘ٫ঐ੄නکə༆Зʩ
ᜊᅰί዆᜗ഐ࿴ʕাኳ᜗π׳ٙᗫڷf

Էνj

union
{
unsigned char allbyte;
struct
{
unsigned flag0:1; // bit0
unsigned flag1:1; // bit1
unsigned count:3; // bit2~bit4
unsigned :3; // bit5~bit7
}bits;
}byte_member;

ӚϞ܁ѓ count ag1 ag0
   
Bit7€MSB Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0€LSB

allbyte

ν؈ࠅπ՟዆ࡈ Byte ۆ̙˸Դ͜ byte_member.allbyte ਂᛘᄳd߰ࠅπ՟຅ʕٙዹ

ͭٙ bitdԷν bit0 ۆԴ͜ byte_member.bits.flag0 ਂᛘᄳf

ɓছЗʩᜊᅰၾഒ࿁ЗѧᜊᅰΥࣛ͜dɽ௅ʱ݊͜Ը່֛ PIC ʫ௅तࣿᅲπኜ
€SFRٙዹͭЗʩfЗʩ֛ѧٙৎ֐Зѧމ 0dϘಂ܁ѓٙ˙جމ€FSR ٙЗѧ
*8bits+ ਋୅ЗʩdШ݊ܝಂ XC8 ٙو͉ۆܔᙄԴ͜ഐ࿴ЗʩԸԴ͜f

Էνj

/* PORTA ֛ѧ܁ѓ */
extern volatile unsigned char PORTA @ 0xF80;
܁ѓ PORTA Зໄ݊ί 0xF80
/* PORTA Зʩ܁ѓ */
typedef union {
struct {
unsigned RA0:1;
unsigned RA1:1;
unsigned RA2:1;
unsigned RA3:1;
unsigned RA4:1;
unsigned RA5:1;

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