[SOLVED] Replacing shiftOut with hard SPI

hello,
i'm tweaking nokia 5110 lcd's library adafruit more performance. so, want replace shiftout hardware spi.
the original working code :

code: [select]

inline void adafruit_pcd8544::fastspiwrite(uint8_t d) {
   for(uint8_t bit = 0x80; bit; bit >>= 1) {
   *clkport &= ~clkpinmask;
   if(d & bit) *mosiport |=  mosipinmask;
   else        *mosiport &= ~mosipinmask;
   *clkport |=  clkpinmask;
 }
}
//a slower alternative :
inline void adafruit_pcd8544::slowspiwrite(uint8_t c) {
 shiftout(_din, _sclk, msbfirst, c);
}
(line 192 https://github.com/adafruit/adafruit-pcd8544-nokia-5110-lcd-library/blob/master/adafruit_pcd8544.cpp, shiftout alternative line 202)

so replace (i renamed library gamebuino_screen, don't care that)

code: [select]


void gamebuino_screen::begin(uint8_t contrast) {
 spi.begin();
 spi.setbitorder(msbfirst);
 spi.setclockdivider(spi_clock_div64); //to have same clock speed "software" spi
 spi.setdatamode(spi_mode3);
[...]
}

inline void gamebuino_screen::fastspiwrite(uint8_t d) {
 spi.transfer((char)d);
}

and screen acts weirdly... here video :
http://www.youtube.com/watch?v=d6nlib_dlpk
the image moves right @ each frame.
something strange : if bridge pins dc & din (mosi) finger, image stops moving, menu's text not vertically aligned should.

so what's difference between software spi above , hardware spi ? please me

code: [select]

  spi.setdatamode(spi_mode3);


as quick test, try different modes (eg. 0, 1, or 2).

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