Hi, may be you should comment this line instead ( (autoAckEnabled && hwAutoAckDefault) << CC2420_MDMCTRL0_AUTOACK ) | but i just looked the code. -Bill -------------- next part -------------- An HTML attachment was scrubbed... URL: https://www.millennium.berkeley.edu/pipermail/tinyos-help/attachments/20090617/39e71fd8/attachment.htm