CMOSTEK NextGenRF CMT2189B, User Manual

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AN201
Rev 1.5 | 26/91 www.cmostek.com
. . .
P P P P
Interval Interval Interval
P
Interval Interval
D P P
Group1 Group2 Group3
Data of 1 packet
Packet 1 Packet 2 Packet 3 Packet 4
. . .
. . . P
Interval Interval
D P D P D
Group1 Group2 Group3
P P P
S i n g l e p a c k e t
transmission
(no group), N=1
D D D D
G r o u p b a s e d
transmission, m groups
with n packets in each
g r o u p . E a c h g r o u p
c o n t a i n 1 P r e a m b l e
(n
≠
1
，
m
≠
1)
D D D D D D D D D D D
Data of 4 packet
（
n=4
）
m data group
D D P
N
D P D D D P
Data of 3 packet
（
n=3
）
m data group
G r o u p b a s e d
transmission, m groups
with n packets in each
g r o u p . E a c h p a c k e t
c o n t a i n s 1 P r e a m b l e
(n
≠
1
，
m
≠
1)
Figure 8. Various Packet Transmission Methods

If Tcycle is disabled, the packet transmission follows the first method as shown in the above figure. If preamble is enabled,
the preamble is fixed at the beginning of each packet.

If both Tcycle and preamble are enabled and PREAMBLE_LOCATION = 1, the packet transmission follows the second
method as shown in the above figure. That is, a preamble appears once in a group locating at the beginning of each group
and preamble appears M times (M = TXCYCLE) within one transmission cycle.

If Both Tcycle and preamble are enabled, and PREAMBLE_LOCATION = 0, the packet transmission follows the third
method as shown in the above figure. That is, a preamble appears once in a group locating at the beginning of each group
and preamble appears m*n (TXCYCLE * PKT_NUM) within one transmission cycle.
Notes
1. In the above figure, P = Preamble
，
D = Sync/Head + Addr/ID + Key Value + LBD Stop Bit.
2. If Preamble is disabled, preamble is not sent.
3. If Interval is disabled, interval is not sent.
4. If Tcycle is disabled, preamble_location is configured to 0.
5. If Tcycle is disabled, Tcycle is configured to 0.
Table 21. Tcycle Configuration Register
Register Name Bits R/W Bit Name Function Description
CUS_PKT1
(0x08)
2 RW PREAMBLE_LOCATION
When Tcycle is enabled, it is the location of Preamble
in the packet structure.
0: In one cycle, each Packet contains 1 Preamble, i.e.
in one cycle, N Packets contain N Preambles.
1: In one cycle, only 1 Preamble is included, which is
only in the first Packet.
7 RW TCYCLE_EN
Tcycle Enable bit:
0
：
Disable
1
：
Enable