added

mylibs/841sleep.h

@@ -0,0 +1,57 @@
+/*
+  Macros for easier sleep mode management
+  For Attiny841 only
+*/
+
+#include <avr/sleep.h>
+#include <avr/wdt.h>
+#include <avr/interrupt.h>
+
+#include "841vcc.h"
+
+#ifndef SLEEPMODE_8441_H
+#define SLEEPMODE_8441_H
+
+#ifndef SLEEPMODE
+  #define SLEEPMODE SLEEP_MODE_PWR_DOWN
+#endif
+
+#ifndef SLEEP_DURATION_BITS
+#define SLEEP_DURATION_BITS (_BV(WDP0) | _BV(WDP3)) // 8s
+#endif
+
+// define sleep mode
+// disable analog comparator 0 and 1
+// disable SPI
+// unlock Watchdog configuration register
+// enable the WD interrupt, set watchdog timeout prescaler value (interrupt period)
+// unlock clock configuration change
+// change clock prescaler to 8
+#define sleep_setup()                        \
+  set_sleep_mode(SLEEPMODE);                 \
+  ACSR0A |= _BV(ACD0);                       \
+  ACSR1A |= _BV(ACD1);                       \
+  CCP = 0xD8;                                \
+  WDTCSR = _BV(WDIE) | SLEEP_DURATION_BITS;  \
+  CCP = 0xD8;                                \
+  CLKPR = (_BV(CLKPS0) | _BV(CLKPS1));
+
+// FIXME: check!
+// PRR = 0xFF;
+
+
+// go into sleep mode and wake up after wtd timeout
+// also disable SPI
+#define sleep_enter()  \
+  adc_disable();       \
+  SPCR   &= ~_BV(SPE); \
+  sleep_enable();      \
+  sleep_mode();        \
+  sleep_disable();     \
+  SPCR = (1<<SPE)
+
+// nothing extra to do on wake up, just wake up
+#define sleep_vect() ISR(WDT_vect){}
+
+
+#endif