sm8211m Nippon Precision Circuits Inc, (NPC), sm8211m Datasheet - Page 5

• Manufacturer Part Number: sm8211m
• Description: Pocsag Decoder For Pagers
• Manufacturer: Nippon Precision Circuits Inc, (NPC)

FUNCTIONAL DESCRIPTION
Receive Format
The receive format conforms to CCIR RPC No. 1
(POCSAG).
Sync signal (SC)
The sync signal is a continuous code word in the
received signal, used for word synchronization. It
comprises 31 bits in an M-series bit pattern plus one
Table 1. Sync code word
Bit number
1
2
3
4
5
6
7
8
Continuous 576-bit "1,0" bit pattern
... 1 0 1 0 1 0 1 0 1 0 ...
Preamble
Bit value
0
1
1
1
1
1
0
0
Bit number
10
11
12
13
14
15
16
9
Sync code word
SC
SC
Figure 1. Receive signal format
Bit value
0
Frame number
1
1
0
1
0
0
1
0
SM8211M
1
1 code word (32 bits)
Bit number
even-parity bit, making a 32-bit signal. The sync
code word pattern is shown in table 1.
2
17
18
19
20
21
22
23
24
1st batch
1 frame (= 2 code words)
3
Bit value
4
0
0
0
1
0
1
0
1
NIPPON PRECISION CIRCUITS—5
5
Bit number
6
25
26
27
28
29
30
31
32
7
Bit value
SC
successive
2nd and
batches
1
1
0
1
1
0
0
0