-            if out_end-out_start != 1:
-                raise NotImplementedError("Currently can only write a single byte in writeto_then_readfrom")
-            readin = self._i2c_bus.read_i2c_block_data(address, buffer_out[out_start:out_end][0], in_end-in_start)
+            readin = self._i2c_bus.read_i2c_block_data(address, buffer_out[out_start:out_end], in_end-in_start)