Specification of RTRM08 Transceiver Module Easywave I2C - ELDAT

Specification
Index 1.01
Project No.
RF-Products, Controller RTRM08 Transceiver Module Easw I 2 C Page 20
Development
Production S. Schreiber 2007-08-24
7007
and RX_USERDATA1 registers contain the opaque user data which is associated with the channel
number.
• The module does not receive further valid learned Easywave telegrams. The RX_TEL_VALID-bit
in the RX_STATUS register is set to 0 now; it indicates the end of a learned Easywave telegram.
(For example, the user has released the button of a transmitter.)
• The I 2 C master can read out the channel number, the button number, and the opaque user data if the
RX_TEL_VALID-bit in the RX_STATUS register is 1.
While the RX_TEL_CHANGED bit is 1, the transceiver module won't change the contents of the
RX_CHANNEL and RX_BUTTON registers and of the RX_TEL_VALID bit in the RX_STATUS register even if
another Easywave telegram is received.
• If the I 2 C master reads the RX_ACK register, the transceiver module drops the channel number and the
button number of the received telegram. The RX_ACK register also can be read in a single read transfer
with the other registers mentioned above. If one of the above conditions has occurred meanwhile, the
/ REQ output remains low, and the RX_TEL_CHANGED-bit in the RX_STATUS register remains 1. Otherwise
the transceiver module clears the RX_TEL_CHANGED-bit in the RX_STATUS register and the / REQ output
goes high. (For example, a user holds down the button of a transmitter or the user does not push any
button.) If the / REQ output goes high, the transceiver module guarantees that it happens before the I 2 C
read transfer from the RX_ACK register on the I 2 C-bus terminates.
The green LED blinks as long as the transceiver module receives any Easywave telegram. (The LED is
drawn on Figure 1 on page 4).
transceiver
/REQ
output
RX_TEL_-
CHANGED
RX_TEL_-
VALID
I 2 C-bus
high
low
1
0
1
0
RX
on
receive
telegrams #1
read
data:
begin
telegr.
#1
RX
on
read
data:
end of
telegr.
Figure 11 Sequence when receiving Easywave telegrams
receive
telegrams #2
read
data:
begin
telegr.
#2
receive
telegrams #3
read
data:
begin
telegr.
#3
RX
on
read
data:
end of
telegr.
A master should perfom the following steps if it wants to receive Easywave telegrams subsequent it has set
the RX_MODE-register to the RX_RQ or RX_PL value:
• Wait until the / REQ output goes low (RX_RQ only) or wait until the RX_TEL_CHANGED-bit in the