document sloppy HW ACK timestamping

[tinyos-2.x.git] / tos / chips / rf2xx / rf230 / README

diff --git a/tos/chips/rf2xx/rf230/README b/tos/chips/rf2xx/rf230/README
index 0f4054c58789a55ff11c6fb4ba0d46260c47a428..e73a761143334966bed1d5d1b0a196a34453745b 100644 (file)
--- a/tos/chips/rf2xx/rf230/README
+++ b/tos/chips/rf2xx/rf230/README
@@ -33,7 +33,7 @@ RF230ActiveMessageC.
 RF230_CRCBYTE_COMMAND:
 
 This is the command used to calculate the CRC for the RF230 chip, since it 
-does not support hardware CRC checking (in rev A)
+does not support hardware CRC checking (in rev A).
 
 RF230_SLOW_SPI:
 
@@ -46,3 +46,17 @@ RF230_RSSI_ENERGY:
 If you define this, then the content of the RF230_PHY_ED_LEVEL is queried 
 instead of the RSSI value for eahc incoming message. This value can be 
 obtained with the PacketRSSI interface.
+
+RF230_HARDWARE_ACK
+
+If you define this, then the radio stack will use hardware acknowledgements
+and address recognition. In particular, you will not be able to snoop on
+onther messages. The load on the CPU is reduced, you should be able to send
+more messages under heavy load. Note, that the PacketRSSI interface will
+return the energy level (and not the rssi value) of received packet.
+
+RF230_HWACK_SLOPPY_TIMESTAMP
+
+If you define this, then the code that calculates the time stamp of the SFD
+from a single interrupt at the end of the message reception will not use
+floating point computation, which will be faster but less precise.