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sbus_poke16(0x6c, sbus_peek16(0x6c) & ~(1 << pinOffSet)); -Read 16 bits IO ports -Create a mask to clear the corresponding bit . (1<< n) is equivalent to ( 2 power n) and the ~ is the complement. Ex: ~(1<<(31-21)) = 0xBFF -And write it back. The best way to deal using fast access with multiple unorder DIO pins is to create a complement Mask of all the DIO you want to manipulate and a Lookup Table with all the possibilities. Using the complement mask to knock off DIO bits and the Table to set them will be very effective. This is an example for a 4 bits LCD display. The DIOs don’t need to be in sequence, it could be any DIO. Ex: #include <stdlib.h> #include <stdio.h> #include <math.h> #define NUMBER_OF_DIO 4 // set the TABLE_SIZE to 2 power DIO_NUMBER #define TABLE_SIZE 16 // specify you DIO (from 21 to 36) . The first will be the LSB. int DIO[NUMBER_OF_DIO]= { 21,22,31,32}; unsigned short Table[TABLE_SIZE]; unsigned short Mask; void initTable(void) { int loop; int bits; unsigned short _utemp; int TableSize= (long) powl(2,NUMBER_OF_DIO); // now let’s create the table for(loop=0;loop<TABLE_SIZE;loop++) { unsigned short utemp=0; for(bits=0;bits<NUMBER_OF_DIO;bits++) if(loop & (1<<bits)) utemp|= 1<< (DIO[bits]-21); Table[loop]=utemp; } // and the Mask; Mask = ~Table[TABLE_SIZE-1]; } // and the write function void write4bits(unsigned char value) { if(value >= TABLE_SIZE) return; sbus_poke16(0x6c,(sbus_peek16(0x6c) & Mask) | Table[value]); } This is just an example. Daniel Sorry about the previously deleted post. I didn't check the code first but now it is ok __._,_.___ Posted by: __,_._,___ |