ST METERS AND MORE UM2241, Руководство пользователя

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Configuring the ST75MM UM2241
24/26 DocID030767 Rev 1
Byte Field Bit Sub-field Description and values
3
RX high
channel
Receiving mode for higher channel
0: FSK modulation
1: any PSK modulation
4-
7
Reserved -
3-5 Reserved - Reserved {0x3B, 0x58, 0x9B}
4.2 MAC configuration (MIB index 3)
In order to configure the ST75MM modem to work in the normal MAC mode the MIB object
3 shall be programmed with the following string:
{0x01, 0x00}
Corresponding to the following configuration (selected values are in bold ).
Table 18: MAC configuration values for CENELEC 132.5 kHz operations
Byte Field Bit Sub-field Description and values
0 RX mode - -
0: RX disable
1: RX normal
2 to 255: reserved
1 TX mode - -
0: TX disable
1: TX normal
2 to 255: reserved
4.3 Manufacturer data (MIB index 6)
The modem identifier and the modem address selection are outside the scope of this
document, anyhow, as soon as the manufacturer, or the network administrator, or any
competent authority, have assigned those values, the host controller shall program it inside
the modem by writing the MIB object 6. Until this operation the modem will be capable only
of receiving broadcast frames, as no default valid address has been programmed into the
ST75MM.
In case no device ID is available, a dummy value could be used, as the only parameter
which influences the communication is ACA.
4.4 Custom frequencies (MIB index 23)
In order to configure the ST75MM modem to work as a single channel receiver in the
CENELEC 132.5 kHz band the MIB object 2 shall be programmed with the following string:
{0x08, 0x7A, 0xE1, 0x07, 0x0A, 0x3D,
0x07, 0xC2, 0x8F, 0x09, 0x5C, 0x29,
0x00, 0x00, 0x00, 0x00, 0x00}
Which sets as a channel pair the couple (132.5 kHz, 110 kHz), as in single channel
operations the ST75MM modem only operates in the high frequency channel.