From 60d4bee9a67eefb7de395c008de76111183a3445 Mon Sep 17 00:00:00 2001
From: Stefan Rupp <struppi@struppi.name>
Date: Mon, 5 Jan 2015 04:17:07 +0100
Subject: [PATCH] changed flush function in led1642gw, hope this is easier to
 understand

---
 led1642gw.c | 38 ++++++++++++++++++--------------------
 1 file changed, 18 insertions(+), 20 deletions(-)

diff --git a/led1642gw.c b/led1642gw.c
index 617ea73..dcaded2 100644
--- a/led1642gw.c
+++ b/led1642gw.c
@@ -209,27 +209,25 @@ void led1642gw_flush(void)
   uint8_t ic;
 
   // for each of the first 15 channels, do the following:
-  for (channel=0; channel<NUM_LED1642GW_CHANNELS-1; channel++) {
-	  // shift data throught the first n-1 ICs with write_no_command
-	  for (ic=0; ic<(NUM_LED1642GW_ICs-1); ic++) {
-		  write_no_command(ledbuffer[channel+(NUM_LED1642GW_CHANNELS*ic)]);
-	  }
-	  // then, when the brightness data has propagated through the
-	  // shift registers, write all data into the DATA LATCH of
-	  // all of the ICs.
-	  write_data_latch(ledbuffer[channel+(NUM_LED1642GW_CHANNELS*ic)]);
+  for (channel=0; channel<NUM_LED1642GW_CHANNELS; channel++) {
+    // shift data throught the first n-1 ICs with write_no_command
+    for (ic=0; ic<(NUM_LED1642GW_ICs-1); ic++) {
+      write_no_command(ledbuffer[channel+(NUM_LED1642GW_CHANNELS*ic)]);
+    }
+    // then, when the brightness data has propagated through the
+    // shift registers, write all data into the DATA LATCH of
+    // all of the ICs.
+    // for the 16th channel, we don't write to the DATA LATCH, but
+    // to the CLOBAL data latch.
+    // once more, we do the trick with write_no_command, to 
+    // shift data through all the ICs
+    if (channel <= NUM_LED1642GW_CHANNELS-1) {
+      write_data_latch(ledbuffer[channel+(NUM_LED1642GW_CHANNELS*ic)]);
+    }
+    else {
+      write_global_latch(ledbuffer[(ic*NUM_LED1642GW_CHANNELS)-1]);
+    }
   }
-  // for the 16th channel, we don't write to the DATA LATCH, but
-  // to the CLOBAL data latch.
-  // once more, we do the trick with write_no_command, to 
-  // shift data through all the ICs
-  for (ic=1; ic<NUM_LED1642GW_ICs; ic++) {
-	  write_no_command(ledbuffer[(ic*NUM_LED1642GW_CHANNELS)-1]);
-  }
-  // than, at last, write data to the global latch, to force 
-  // the ICs to update their brightness data from the DATA LATCHES.
-  write_global_latch(ledbuffer[(ic*NUM_LED1642GW_CHANNELS)-1]);
-
 }