Changeset 2977

Timestamp:

May 16, 2012 1:03:21 PM (12 months ago)

Author:

quozl

Message:

OLPC XO-1.75 - IDT1338 DS1338 RTC SRAM clear, check for a two byte signature at the end of SRAM, and if it is missing clear the century byte (not maintained by the RTC), and the area we are using for "CMOS".

File:

• cpu/arm/olpc/rtc.fth (modified) (3 diffs)

cpu/arm/olpc/rtc.fth

@@ -22 +22 @@
 headerless
 
+: ?clear
+   h# 3f rtc@  h# 3e rtc@  bwjoin  h# 55aa  <>  if
+      h# 20 8 rtc!                     \ century
+      h# 20 h# 10  do  0 i rtc!  loop  \ wipe cmos@ cmos! area
+      h# 55aa  wbsplit  h# 3e rtc!  h# 3f rtc!
+      ." RTC SRAM cleared" cr
+   then
+;
+
 headers
 : open  ( -- okay )
@@ -30 +39 @@
    \ Ensure that the Clock Halt bit is off
    dup h# 80 and  if           ( value )
-      \ Clear century
-      h# 20 8 rtc!
       \ Turn off Clock Halt
       h# 7f and 0 rtc!         ( )
@@ -41 +48 @@
       drop true                ( true )
    then                        ( okay? )
+   ?clear
 ;
 : close  ( -- )