User's Manual

Boomer II User Manual & Integrator’s Guide ______________________________________________ SDK SCRAPI
BM210012WT27 151 Wavenet Technology
Definitions for all SCR message structures can be found in the file
scrapi.h. (SCR SDK)
Network Independent Messages
The SCR API provides several network independent message types.
These message types represent basic functions within the SCR protocol
that are applicable to all DataTAC network types. The SCR API
encodes and decodes these message types as the appropriate message
for the correct network type, as given in the call to the scr_Init()
function.
It is recommended that you use these network independent message
types wherever possible, to enhance the portability of the code between
different DataTAC network versions.
The three network independent message types are listed here:
SCR_FROM_NET Generic From Network message. This is used
for receiving data from a wireless device.
Depending on the network setting, this
corresponds to either a Basic Outbound (OB)
message for DataTAC 4000 networks, or a
Message Indication (MI) for DataTAC 5000 or
6000 networks.
SCR_TO_NET Generic To Network message. This is used for
sending data to a wireless device. Depending on
the network setting, this will be encoded as
either a Basic Inbound (IB) message for
DataTAC 4000 networks, or a Host Request
(HR) message for DataTAC 5000 or 6000
networks.
SCR_ACK Generic Acknowledgment message. This is
used to receive an acknowledgment for data
sent to a wireless device.
SCR_TO_NET messages may be passed to scr_Encode(), and they will
be encoded as the appropriate message type for the current network, as
set in the call to scr_Init(). When a received packet is decoded using
scr_Decode(), it converts the received packet to an SCRMsg structure.
The received messages are decoded for the current network type, and
stored in the SCRMsg structure as their actual message type. However,
the definition of the generic From Network message structure,
SCRfromnet, is exactly the same as both the Message Indication (MI)
message structure, SCRmi, and the Basic Outbound (OB) message
structure, SCRob. Because of this, the decoded message structure may
be interpreted as any of these structures. Similarly, the message type
values SCR_FROM_NET, SCR_MI, and SCR_OB are defined to be
the same value.
Also, the message types SCRack, SCRhc, and SCRab are all the same,
and the message-type constants SCR_ACK, SCR_HC, and SCR_AB
are all the same, and so may be interpreted interchangeably.