Diff: led_strip_write_color.s

Revision:

20:656bbcb64e3b

Parent:

19:46d7ab0ba3e7

Child:

21:87fd6273e0ff

--- a/led_strip_write_color.s	Wed Oct 09 01:13:49 2013 +0000
+++ b/led_strip_write_color.s	Wed Nov 13 21:16:24 2013 +0000
@@ -21,22 +21,21 @@
     ; Additionally, we use these registers:
     ;   R4:  temporary register
     ;   R5:  temporary register
-    ;   R6: shift register that holds the 24-bit color
+    ;   R6:  shift register that holds the 24-bit color
     ;   R7:  the number of bits we still need to send
     ;   R13: Link Register, holds return addresses.
 
     ; Push those registers so we can restore them later.
     push {r4, r5, r6, r7, lr}
 
+    ldrb r6, [r0, #1]  ; Load green.
+    lsls r6, r6, #24   ; Put green in MSB of r6.
     ldrb r4, [r0, #0]  ; Load red.
-    lsls r4, r4, #24
-    mov r6, r4         ; Put red in MSB of r6.
-    ldrb r4, [r0, #1]  ; Load green.
     lsls r4, r4, #16
-    orrs r6, r6, r4    ; Put green in r6.
+    orrs r6, r6, r4    ; Put red in r6.
     ldrb r4, [r0, #2]  ; Load blue.
     lsls r4, r4, #8
-    orrs r6, r6, r4    ; Put blue in MSB of r6.
+    orrs r6, r6, r4    ; Put blue in LSB of r6.
    
     ; On the Cortex M0 we simply did:
     ;    ldr r6, [r0]       ; Read the color.  Now we have:     xxBbGgRr