Interfacing and Controlling the RIM 801D Protocol support: NCL Protocol
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RIM 801D OEM Radio Modem – Integrator’s Guide
The user header consists of network routing information and is dependent
on the particular network routing information being used.
The DataTAC Open Protocol Specification on DataTAC Messaging
(68P04025C10-O) contains information on user header formats for
DataTAC networks.
NCL Protocol
The NCL, Native Control Language, protocol is a link layer protocol,
designed to govern communication between a radio modem and a host
device over a serial cable link. NCL carries SDUs to and from the radio, as
well as any radio control instructions. NCL is available in all DataTAC
radios, including the RIM 801D.
SDUs are carried inside NCL frames. In addition to the data, the NCL frame
contains start and end characters. When the radio modem and host system
exchange an NCL frame, considerable handshaking is taking place in order
to ensure reliable transfer over the serial link.
The DataTAC Open Protocol Specifications on Native Control Language
(NCL) (68P04025C10-O) includes a complete protocol specification and
contains detailed information about NCL frames and frame types.
Radio Access Protocol (RAP)
RAP (Radio Access Protocol) is a simple, connectionless link layer
protocol, designed to communicate with and control the RIM 801D radio
modem, and to send and receive information over the wireless network
A RAP program transfers data packets (e.g. SDUs) and radio control
commands between an embedded system and the RIM 801D over an
asynchronous serial port, using RAP’s framed link protocol. The RAP
program is not concerned with the transfer of data between the RIM 801D
and a DataTAC network base station, as the RIM 801D completely handles
transmission and reception.
