diff --git a/st7735.c b/st7735.c
index e864e97..9b51bbd 100644
--- a/st7735.c
+++ b/st7735.c
@@ -308,29 +308,36 @@ void st7735_fill_rect(uint8_t x, uint8_t y, uint8_t w, uint8_t h, uint16_t color
 
 
 void st7735_draw_bitmap(uint8_t x, uint8_t y, PGM_P bitmap) {
-	if(x >= st7735_width || y >= st7735_height) {
-		return;
-	}
-
 	uint8_t w = pgm_read_word(bitmap);
 	bitmap += 2;
 	uint8_t h = pgm_read_word(bitmap);
 	bitmap += 2;
+        uint8_t max_x = x + w - 1;
+        uint8_t max_y = y + h - 1;
 
-	if((x + w - 1) >= st7735_width) {
-		return;
-	}
-	if((y + h - 1) >= st7735_height) {
+	if(x >= st7735_width || y >= st7735_height) {
 		return;
 	}
 
-	st7735_set_addr_win(x, y, x + w - 1, y + h - 1);
+	if(max_x >= st7735_width) {
+            max_x = st7735_width - 1;
+	}
+
+	if(max_y >= st7735_height) {
+            max_y = st7735_height - 1;
+	}
+
+	st7735_set_addr_win(x, y, max_x, max_y);
 
 	st7735_set_rs();
 	spi_unset_cs();
 
 	for(uint8_t i = 0; i < h; i++) {
 		for(uint8_t j = 0; j < w; j++) {
+                        if((x + j) >= st7735_width || (y + i) >= st7735_height) {
+                            bitmap += 2;
+                            continue;
+                        }
 			uint16_t color = pgm_read_word(bitmap);
 			st7735_write_color(color);
 			bitmap += 2;
@@ -343,19 +350,22 @@ void st7735_draw_bitmap(uint8_t x, uint8_t y, PGM_P bitmap) {
 void st7735_draw_mono_bitmap(uint8_t x, uint8_t y, PGM_P bitmap, uint16_t color_set, uint16_t color_unset) {
 	uint8_t w = pgm_read_byte(bitmap++);
 	uint8_t h = pgm_read_byte(bitmap++);
+        uint8_t max_x = x + w - 1;
+        uint8_t max_y = y + h - 1;
 
 	if(x >= st7735_width || y >= st7735_height) {
 		return;
 	}
 
-	if((x + w - 1) >= st7735_width) {
-		return;
-	}
-	if((y + h - 1) >= st7735_height) {
-		return;
+	if(max_x >= st7735_width) {
+            max_x = st7735_width - 1;
 	}
 
-	st7735_set_addr_win(x, y, x + w - 1, y + h - 1);
+	if(max_y >= st7735_height) {
+            max_y = st7735_height - 1;
+	}
+
+	st7735_set_addr_win(x, y, max_x, max_y);
 
 	st7735_set_rs();
 	spi_unset_cs();
@@ -365,9 +375,13 @@ void st7735_draw_mono_bitmap(uint8_t x, uint8_t y, PGM_P bitmap, uint16_t color_
 	for(uint8_t i = 0; i < h; i++) {
 		for(uint8_t j = 0; j < w; j++) {
 			if(bit_pos % 8 == 0) {
-				byte = pgm_read_byte(bitmap++);
+                            byte = pgm_read_byte(bitmap++);
 			}
 
+                        if((x + j) >= st7735_width || (y + i) >= st7735_height) {
+                            bit_pos++;
+                            continue;
+                        }
 			if(byte & (1 << (bit_pos % 8))) {
 				st7735_write_color(color_set);
 			}
@@ -379,5 +393,4 @@ void st7735_draw_mono_bitmap(uint8_t x, uint8_t y, PGM_P bitmap, uint16_t color_
 	}
 
 	spi_set_cs();
-
 }