TURNELL, D. J.; http://lattes.cnpq.br/9509471389644717; TURNELL, David John.
Resumo:
This work describes the design and implementation of a
communications front-end processor (PFC) f o r MAP type networks. In the
f i r s t part of t h i s work i s a presentation of the development of the
hardware in the form of a board for the PP (Processador Preferencial)
general purpose super-microcomputer developed by Telebras. This board
contains a 16 b i t microprocessor, a network controller IC, and up to 512
kbytes of memory. The second part of t h i s work describes the developed
multi-tasking nucleus, called the Executive, which is designed
s p e c i f i c a l l y for t h i s hardware and optimized for real-time operation and
the support of the implantation of the protocols which follow the RM
OSI/ISO standard. The Executive offers task management services, intertask
communication services, timing services and dynamic memory
allocation services. The third part of this work describes the
implementation of the layers LLC (Logic Link Control) and MAC (Media
Access Control) f o r the i n s t a l l a t i o n of protocols following a mini-MAP
architecture. These two layers are implemented i n the form of a single
task which executes under the Executive.