diff options
Diffstat (limited to 'USBLCD.c')
| -rw-r--r-- | USBLCD.c | 91 |
1 files changed, 65 insertions, 26 deletions
@@ -1,4 +1,4 @@ -/* $Id: USBLCD.c,v 1.10 2003/07/24 04:48:09 reinelt Exp $ +/* $Id: USBLCD.c,v 1.11 2003/08/16 07:31:35 reinelt Exp $ * * Driver for USBLCD ( see http://www.usblcd.de ) * This Driver is based on HD44780.c @@ -22,6 +22,9 @@ * * * $Log: USBLCD.c,v $ + * Revision 1.11 2003/08/16 07:31:35 reinelt + * double buffering in all drivers + * * Revision 1.10 2003/07/24 04:48:09 reinelt * 'soft clear' needed for virtual rows * @@ -94,13 +97,13 @@ #define CHARS 8 static LCD Lcd; - -int usblcd_file; - static char *Port=NULL; -static char Txt[4][40]; +static int usblcd_file; + +static char *FrameBuffer1=NULL; +static char *FrameBuffer2=NULL; -static unsigned char Buffer[1024]; +static unsigned char *Buffer; static unsigned char *BufPtr; static void USBLCD_send () @@ -195,19 +198,15 @@ static void USBLCD_define_char (int ascii, char *buffer) int USBLCD_clear (int full) { - int row, col; - - for (row=0; row<Lcd.rows; row++) { - for (col=0; col<Lcd.cols; col++) { - Txt[row][col]='\t'; - } - } - + + memset (FrameBuffer1, ' ', Lcd.rows*Lcd.cols*sizeof(char)); bar_clear(); - if (full) + if (full) { + memset (FrameBuffer2, ' ', Lcd.rows*Lcd.cols*sizeof(char)); USBLCD_command (0x01); // clear display - + } + return 0; } @@ -248,6 +247,21 @@ int USBLCD_init (LCD *Self) Self->cols=cols; Lcd=*Self; + // Init the command buffer + Buffer = (char*)malloc(1024); + if (Buffer==NULL) { + error ("USBLCD: coommand buffer could not be allocated: malloc() failed"); + return -1; + } + + // Init the framebuffers + FrameBuffer1 = (char*)malloc(Lcd.cols*Lcd.rows*sizeof(char)); + FrameBuffer2 = (char*)malloc(Lcd.cols*Lcd.rows*sizeof(char)); + if (FrameBuffer1==NULL || FrameBuffer2==NULL) { + error ("USBLCD: framebuffer could not be allocated: malloc() failed"); + return -1; + } + if (USBLCD_open()!=0) return -1; @@ -271,7 +285,7 @@ void USBLCD_goto (int row, int col) int USBLCD_put (int row, int col, char *text) { - char *p=&Txt[row][col]; + char *p=FrameBuffer1+row*Lcd.cols+col; char *t=text; while (*t && col++<=Lcd.cols) { @@ -289,9 +303,8 @@ int USBLCD_bar (int type, int row, int col, int max, int len1, int len2) int USBLCD_flush (void) { - char buffer[256]; - char *p; - int c, row, col; + int row, col, pos1, pos2; + int c, equal; bar_process(USBLCD_define_char); @@ -299,31 +312,57 @@ int USBLCD_flush (void) for (col=0; col<Lcd.cols; col++) { c=bar_peek(row, col); if (c!=-1) { - Txt[row][col]=(char)c; + FrameBuffer1[row*Lcd.cols+col]=(char)c; } } for (col=0; col<Lcd.cols; col++) { - if (Txt[row][col]=='\t') continue; + if (FrameBuffer1[row*Lcd.cols+col]==FrameBuffer2[row*Lcd.cols+col]) continue; USBLCD_goto (row, col); - for (p=buffer; col<Lcd.cols; col++, p++) { - if (Txt[row][col]=='\t') break; - *p=Txt[row][col]; + for (pos1=col++, pos2=pos1, equal=0; col<Lcd.cols; col++) { + if (FrameBuffer1[row*Lcd.cols+col]==FrameBuffer2[row*Lcd.cols+col]) { + // If we find just one equal byte, we don't break, because this + // would require a goto, which takes one byte, too. + if (++equal>2) break; + } else { + pos2=col; + equal=0; + } } - USBLCD_write (buffer, p-buffer); + USBLCD_write (FrameBuffer1+row*Lcd.cols+pos1, pos2-pos1+1); } } USBLCD_send(); + memcpy (FrameBuffer2, FrameBuffer1, Lcd.rows*Lcd.cols*sizeof(char)); + return 0; } int USBLCD_quit (void) { + info("USBLCD: shutting down."); USBLCD_send(); + debug ("closing port %s", Port); close(usblcd_file); + + if (Buffer) { + free(Buffer); + Buffer=NULL; + } + + if (FrameBuffer1) { + free(FrameBuffer1); + FrameBuffer1=NULL; + } + + if (FrameBuffer2) { + free(FrameBuffer2); + FrameBuffer2=NULL; + } + return 0; } |