1 files changed, 15 insertions, 0 deletions

diff --git a/i2c.s b/i2c.s
new file mode 100644
index 0000000..83ef974
--- /dev/null
+++ b/i2c.s
@@ -0,0 +1,15 @@
+i2cwait:
+	in r17, TWCR
+	sbrs r17, TWINT
+	rjmp i2cwait
+; r16 : addr
+i2cstart:
+	ldi r17, (1 << TWSTA) | (1 << TWEN) | (1 << TWINT)
+	out TWCR, r17
+	rcall i2cwait
+	out TWDR, r16
+	andi r17, ~(1 << TWSTA)
+	out TWCR, r17
+	rcall i2cwait
+; r16: data 
+writebyte: