PR
EL
IMI
NA
RY
SW71122
MLX71122 RF Receiver
Programming Software Manual
39011 71122 01
Page 4 of 21
SW71122-Manual
Rev. 004
Aug/11
1
General Description
The PC programming software can be used to control the operational modes of the MLX71122 RF receiver at
its Serial Programming Interface (SPI) through the three pins A/SCLK, B/SDTA and C/SDEN. The pin
SPISEL must be at logic HIGH in order to set the MLX71122 to SPI mode. Otherwise the receiver operates in
stand-alone (or ABC) mode and cannot be programmed via the three pins A/SCLK, B/SDTA and C/SDEN.
In SPI mode, it is possible to write in and read out the seven control registers R0 to R6. Register R7 is a
read-only register for status information. In ABC mode, 8 predefined frequency channels between 369.5 MHz
and 395.9 MHz can be selected by parallel programming at the three pins A/SCLK, B/SDTA and C/SDEN.
A block diagram of the receiver is shown below.
The following tables show the functionality of the three digital control pins that are used for general operating
mode selection.
Pin
Value
Function
0
ABC mode - stand-alone mode, 8 pre-defined frequencies
SPISEL
1
SPI mode - programmable mode, full control via SPI
Pin
Value
SPISEL
Function
0
FSK receive mode
0
1
no effect
0
ASK receive mode
MODSEL
1
1
no effect
0
Receiver in shutdown mode
0
1
Receiver in last programmed operational mode
0
Receiver in receive mode
ENRX
1
1
Receiver in receive mode
FSK
DEMOD
Control
Logic
M
O
D
S
E
L
SLCSEL
BIAS
E
N
R
X
R
B
IA
S
V
E
E
A
N
A
V
C
C
D
IG
V
E
E
D
IG
OA2
DFO
OA1
PKDET+
PKDET
_
SLC
PDP
PDN
DTAO
D
F
2
D
F
1
29
27
26
30
25
32
28
22
20
16
21
S
P
IS
E
L
A
/S
C
L
K
B
/S
D
T
A
C
/S
D
E
N
17
18
19
7
10
200k
200k
SW2
SW1
2
0
0
k
1
M
1
M
ASK
FSK
L
N
A
O
LNA
V
E
E
L
N
A
V
C
C
A
N
A
LNAI
4
3
31
2
1
V
C
C
V
C
O
V
E
E
V
C
O
14
11
M
F
O
23
R
counter
N / A
counter
PFD
VCO
LF
CP
RO
LO2DIV
V
E
E
IF
9
M
IX
N
M
IX
P
R
S
S
I
IFA
LO2
IF2
IF1
LO1
MIX1
MIX2
IFF
5
6
8
L
F
15
R
O
I
24
TNK1
TNK2
12 13
