David Knight / PololuLedStrip

This library lets you control the addressable RGB LED strips from Pololu Robotics. Forked to add selectable colour order (Support RGB or GRB Leds)

Fork of PololuLedStrip by David Grayson

Diff: led_strip_write_color.s

Revision:
4:d3b60bd43811
Parent:
0:06475317f283
Child:
5:690fdfb595de
--- a/led_strip_write_color.s	Wed Feb 27 02:45:31 2013 +0000
+++ b/led_strip_write_color.s	Thu Feb 28 00:42:44 2013 +0000
@@ -2,7 +2,7 @@
     EXPORT led_strip_write_color
 
 led_strip_write_color
-    push    {r12, r7}
+    push    {r4, r12, r7}
    
     ldr r12, [r0]      ; Read the next color.
     rbit r12, r12      ; Reverse the order of the bits.
@@ -156,9 +156,21 @@
     it cs                ; If the bit to send is 1...
     strcs r3, [r2]       ; Drive the line low.
     
-    nop
-    nop
-    nop
+    ldr r4, =delay_region
+    add r4, r4, 34*2
+    blx r4
+    
+    sub r7, r7, #1               ; Decrement the loop counter.
+    cbz r7, led_strip_asm_end    ; If we have sent 24 bits, go to the end.
+    b send_led_strip_bit         ; Otherwise, go back and send another bit.
+    
+led_strip_asm_end
+    pop {r4, r12, r7}
+    bx lr
+    
+
+delay_region
+    ; The following is 128 no-ops
     nop
     nop
     nop
@@ -166,18 +178,16 @@
     nop
     nop
     nop
-    
-    nop
-    nop
-    nop
-    nop
     nop
     nop
     nop
     nop
     nop
     nop
-    
+    nop
+    nop
+    nop
+
     nop
     nop
     nop
@@ -188,18 +198,19 @@
     nop
     nop
     nop
-    
     nop
     nop
     nop
     nop
     nop
     nop
+
     nop
     nop
     nop
     nop
-    
+    nop
+    nop
     nop
     nop
     nop
@@ -221,6 +232,12 @@
     nop
     nop
     nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
 
     nop
     nop
@@ -232,6 +249,12 @@
     nop
     nop
     nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
 
     nop
     nop
@@ -243,17 +266,12 @@
     nop
     nop
     nop
-
     nop
     nop
     nop
     nop
     nop
     nop
-    nop
-    nop
-    nop
-    nop   
 
     nop
     nop
@@ -265,21 +283,29 @@
     nop
     nop
     nop
-    
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+
     nop
     nop
     nop
     nop
     nop
     nop
-    nop   
-    
-    sub r7, r7, #1               ; Decrement the loop counter.
-    cbz r7, led_strip_asm_end    ; If we have sent 24 bits, go to the end.
-    b send_led_strip_bit         ; Otherwise, go back and send another bit.
-    
-led_strip_asm_end
-    pop {r12, r7}
-    bx lr
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    bx lr    ; return
     
     END
\ No newline at end of file