AMB8426-M_8626-M_MA_EN_V2_4
Page 36 of 48
Released: Nov.2013
Pin out
Selected operating mode
MOD_SEL3 MOD_SEL2 MOD_SEL1 MOD_SEL0
0
0
0
0
User specific configuration
0
0
0
1
S1
0
0
1
0
S1-m
0
0
1
1
S2
0
1
0
0
Reserved
0
1
0
1
T1 meter
0
1
1
0
T1 other
0
1
1
1
T2 meter
1
0
0
0
T2 other
1
0
0
1
C2, T2 Reserved
1
0
1
0
R2 meter
1
0
1
1
R2 other
1
1
0
0
C1 Meter
1
1
0
1
C2 Meter
1
1
1
0
C2 other
1
1
1
1
Reserved
Table 20:
Operating mode selected via MOD_SELx pins
Caution: In the event of periodic toggling, the duration of an operating mode should be
at least 2.5 ms, as otherwise the detection of a preamble cannot be guaranteed!
12 Taking into operation
12.1 Minimal Configuration
Upon shipment the modules are ready for immediate operation. The following pins are required
in the minimal configuration: VCC, GND, UTXD, and URXD.
On shipment the wM-
Bus mode “S2” is selected. The max telegram length is limited to 128 byte.
If the module is to be connected to a PC, a level adapter (TTL to RS232 or USB, see Figure 24)
is required.
12.2 Transfer of Large Amounts of Data
When transmitting larger amounts of data, the limited buffer size of the module must be taken
account of. The data can only be transmitted packet by packet
(no “streaming”).
It is recommended to use the /CTS pin.
