i2c utilities

diff --git a/util/i2cu.lua b/util/i2cu.lua
new file mode 100644 (file)
index 0000000..a7e3fd9
--- /dev/null
+++ b/util/i2cu.lua
@@ -0,0 +1,19 @@
+local self = {}
+
+function self.readn(addr, len)
+  i2c.start(0)
+  if not i2c.address(0, addr, i2c.RECEIVER) then i2c.stop(0) return nil end
+  local v = i2c.read(0, len)
+  i2c.stop(0)
+  return v
+end
+
+function self.writen(addr, ...)
+  i2c.start(0)
+  if not i2c.address(0, addr, i2c.TRANSMITTER) then i2c.stop(0) return nil end
+  i2c.write(0, ...)
+  i2c.stop(0)
+  return true
+end
+
+return self