Datasheet

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Appendix 2: Device Class
The Class of Device/Service(CoD)is a 32 bits number that is made of 3 fields. One field
specifies the service supported by the device. Another field specifies the major device
class, which broadly corresponds to the type of the device. The third field specifies the
minor device class, which describes the device type in more detail.
The Class of Device/Service (CoD) field has a variable format. The format is indicated
using the 'Format Type field' within the CoD. The length of the Format Type field is
variable and ends with two bits different from '11'. The version field starts at the least
significant bit of the CoD and may extend upwards. In the 'format #1' of the CoD
(Format Type field = 00), 11 bits are assigned as a bit-mask (multiple bits can be set)
each bit corresponding to a high level generic category of service class. Currently 7
categories are defined. These are primarily of a 'public service' nature. The remaining 11
bits are used to indicate device type category and other device-specific
characteristics.Any reserved but otherwise unassigned bits, such as in the Major Service
Class field, should be set to 0.
Figure 1.2: The Class of Device/Service field (first format type). Please note the order in
which the octets are sent on the air and stored in memory. Bit number 0 is sent first on
the air.