diff --git a/PLAN b/PLAN
new file mode 100644
index 0000000..0df77f6
--- /dev/null
+++ b/PLAN
@@ -0,0 +1,12 @@
+Dinge die zu tun sind:
+
+- Schaltung entwerfen
+- Schaltung löten
+- blech sägen
+- brett sägen
+- brett aushölen
+- brett fasen
+- innenleben planen
+- impulsgeber befestigen
+- platte und heizelemente befestigen u. bohren
+- brett wachsen
diff --git a/firmware/codefragmente.c b/firmware/codefragmente.c
new file mode 100644
index 0000000..44bef06
--- /dev/null
+++ b/firmware/codefragmente.c
@@ -0,0 +1,49 @@
+
+// alter drehimpulsgebercode, aus marcus-thermometer
+void buttonpoll(){  // runs with 1.2kHz
+	uint8_t l,r,t,flanks,dir;
+	l=BUTTPIN & _BV(BUTTLPIN);
+	r=BUTTPIN & _BV(BUTTRPIN);
+	t=BUTTPIN & _BV(BUTTTPIN);
+
+	// debounce code
+	if (t != butttold && !butttbounce ) {
+		butttold = t;
+		butttbounce = BUTT_BOUNCE;
+		if (t == 0) { // active low
+			buttonevent |= BUTTEV_PUSH;
+		}
+	}
+
+	flanks=0;
+	dir=0;
+	if (l != buttlold) {
+		flanks += 1;
+	}
+	if (r != buttrold) {
+		flanks += 1;
+		dir = 1;
+	}
+	if (flanks == 1){ // we need to have exactly one flank, 0 flanks are no
+					  // change, and 2 flanks are too fast (error)
+		if (l) {
+			dir ^= 1;
+		}
+		if (r) {
+			dir ^= 1;
+		}
+		if ((r && l) || (!r && !l)) {
+			buttoninc += dir ? -1 : 1;
+		}
+	}
+
+	buttlold = l;
+	buttrold = r;
+
+
+	if(butttbounce){
+		butttbounce -= 1;
+	}
+
+}
+