fix screen drawing for aleph.

the aleph screen is mounted upside-down. when porting from aleph to teletype, half the region-drawing functions were inverted, and half were left unchanged (and unused.) now all the functions should draw correctly for both hardwares.

src/screen.c

@@ -1,24 +1,14 @@
-// std 
-/// FIXME: eliminate!!
-#include <stdio.h>
-#include <stdlib.h>
-#include <math.h>
 // ASF
 #include "delay.h"
 #include "gpio.h"
-//#include "util.h"
 #include "intc.h"
 #include "print_funcs.h"
 #include "spi.h"
-//#include "conf_aleph.h"
-// #include "fix.h"
 #include "font.h"
-// #include "global.h"
 #include "screen.h"
 
 //-----------------------------
 //---- variables
-// const U8 lines[CHAR_ROWS] = { 0, 8, 16, 24, 32, 40, 48, 56 };
 
 // screen buffer
 static u8 screenBuf[GRAM_BYTES];
@@ -28,10 +18,6 @@ static u32 i, j;
 static u8* pScr; // movable pointer to screen buf
 static u32 nb; // count of destination bytes
 
-//static u32 pos;
-// fixed-point text buffer
-//static char buf[FIX_DIG_TOTAL];
-
 static void write_command(U8 c);
 static void write_command(U8 c) {
   spi_selectChip(OLED_SPI, OLED_SPI_NPCS);
@@ -57,11 +43,7 @@ void screen_set_rect(u8 x, u8 y, u8 w, u8 h) {
 //------------------
 // al functions
 void init_oled(void) {
-  //U32 i;
-  // volatile u64 delay;
-  //  cpu_irq_disable();
   Disable_global_interrupt();
-  //  delay_ms(1);
   // flip the reset pin
   gpio_set_gpio_pin(OLED_RES_PIN);
   delay_ms(1);
@@ -132,48 +114,60 @@ void init_oled(void) {
   Enable_global_interrupt();
 }
 
+static void writeScreenBuffer(u8 x, u8 y, u8 w, u8 h) {
+  // set drawing region
+  screen_set_rect(x, y, w, h);
+  // select chip for data
+  spi_selectChip(OLED_SPI, OLED_SPI_NPCS);
+  // register select high for data
+  gpio_set_gpio_pin(OLED_DC_PIN);
+  // send data
+  for(i=0; i<(nb); i++) {
+    spi_write(OLED_SPI, screenBuf[i]);
+  }
+  spi_unselectChip(OLED_SPI, OLED_SPI_NPCS);
+}
 
 // draw data given target rect
 // assume x-offset and width are both even!
  void screen_draw_region(u8 x, u8 y, u8 w, u8 h, u8* data) {
   // 1 row address = 2 horizontal pixels
-
   // physical screen memory: 2px = 1byte
   w >>= 1;
   x >>= 1;
   nb = w * h;
-
-  /// the screen is mounted upside down!
-  // copy, pack, and reverse into the top of the screen buffer
-  // 2 bytes input -> 1 byte output
-    // pScr = (u8*)screenBuf + nb - 1;
-    pScr = (u8*)screenBuf;// + x + (y*128) - 1;
+
+  #ifdef MOD_ALEPH // aleph screen is mounted upside down...
+  pScr = (u8*)screenBuf + nb - 1;  
+  x = SCREEN_ROW_BYTES - x - w;
+  y = SCREEN_COL_BYTES - y - h;
+   // copy and pack into the screen buffer
+  // 2 bytes input per 1 byte output
+  for(j=0; j<h; j++) {
+    for(i=0; i<w; i++) {
+	  *pScr = (0xf0 & ((*data) << 4) );
+      data++;
+      *pScr |= ((*data) & 0xf);
+      data++;
+      pScr--;
+    }
+  }
+  #else 
+  pScr = (u8*)screenBuf;
+   // copy and pack into the screen buffer
+  // 2 bytes input per 1 byte output
   for(j=0; j<h; j++) {
     for(i=0; i<w; i++) {
-      // 2 bytes input per 1 byte output
       *pScr = ((*data) & 0xf);
       data++;
       *pScr |= (0xf0 & ((*data) << 4) );
       data++;
       pScr++;
     }
   }
-
-  // flip the screen coordinates 
-  // x = SCREEN_ROW_BYTES - x - w;
-  // y = SCREEN_COL_BYTES - y - h;
-
-  // set drawing region
-  screen_set_rect(x, y, w, h);
-  // select chip for data
-  spi_selectChip(OLED_SPI, OLED_SPI_NPCS);
-  // register select high for data
-  gpio_set_gpio_pin(OLED_DC_PIN);
-  // send data
-  for(i=0; i<(nb); i++) {
-    spi_write(OLED_SPI, screenBuf[i]);
-  }
-  spi_unselectChip(OLED_SPI, OLED_SPI_NPCS);
+  #endif
+
+  writeScreenBuffer(x, y, w, h);
 }
 
 // draw data at given rectangle, with starting byte offset within the region data.
@@ -194,15 +188,16 @@ void screen_draw_region_offset(u8 x, u8 y, u8 w, u8 h, u32 len, u8* data, u32 of
   x >>= 1;
   nb = len >> 1;
 
-  /// the screen is mounted upside down!
-  // copy, pack, and reverse into the top of the screen buffer
-  // 2 bytes input -> 1 byte output
-  pScr = (u8*)screenBuf + nb - 1;
-
+
+  #ifdef MOD_ALEPH // aleph screen is mounted upside down...
+  pScr = (u8*)screenBuf + nb - 1;  
+  x = SCREEN_ROW_BYTES - x - w;
+  y = SCREEN_COL_BYTES - y - h;
+   // copy and pack into the screen buffer
+  // 2 bytes input per 1 byte output
   for(j=0; j<h; j++) {
     for(i=0; i<w; i++) {
-      // 2 bytes input per 1 byte output
-      *pScr = (0xf0 & ((*data) << 4) );
+	  *pScr = (0xf0 & ((*data) << 4) );
       data++;
       if(data > dataEnd) { data = dataStart; }
       *pScr |= ((*data) & 0xf);
@@ -211,22 +206,24 @@ void screen_draw_region_offset(u8 x, u8 y, u8 w, u8 h, u32 len, u8* data, u32 of
       pScr--;
     }
   }
-
-  // flip the screen coordinates 
-  x = SCREEN_ROW_BYTES - x - w;
-  y = SCREEN_COL_BYTES - y - h;
-
-  // set drawing region
-  screen_set_rect(x, y, w, h);
-  // select chip for data
-  spi_selectChip(OLED_SPI, OLED_SPI_NPCS);
-  // register select high for data
-  gpio_set_gpio_pin(OLED_DC_PIN);
-  // send data
-  for(i=0; i<(nb); i++) {
-    spi_write(OLED_SPI, screenBuf[i]);
+  #else 
+  pScr = (u8*)screenBuf;
+   // copy and pack into the screen buffer
+  // 2 bytes input per 1 byte output
+  for(j=0; j<h; j++) {
+    for(i=0; i<w; i++) {
+      *pScr = ((*data) & 0xf);
+      data++;
+      if(data > dataEnd) { data = dataStart; }
+      *pScr |= (0xf0 & ((*data) << 4) );
+      data++;
+      if(data > dataEnd) { data = dataStart; }
+      pScr++;
+    }
   }
-  spi_unselectChip(OLED_SPI, OLED_SPI_NPCS);
+  #endif
+
+  writeScreenBuffer(x, y, w, h);
 }