Echelon LonTal Stack - Manual (Page 17)

LonTalk Stack Developer’s Guide 5
A ShortStack Micro Server is an Echelon Smart Transceiver or Neuron Chip with
ShortStack firmware that implements layers 2 to 5 (and part of layer 6) of the
LonTalk protocol. The host processor implements the application layer (layer 7)
and part of the presentation layer (layer 6). The Echelon Smart Transceiver or
Neuron Chip provides the physical interface for the L ON W ORKS communications
channel. The ShortStack firmware allows you to use almost any host processor
for your device’s application and I/O. The following figure displays the
ShortStack solution for a host-based L
ON
W
ORKS
device.
A simple serial communications interface provides communications between the
ShortStack Micro Server and the host processor. Because a ShortStack Micro
Server can work with any host processor, you must provide the serial driver
implementation, although Echelon does provide the serial driver API and an
example driver for some host processors. An example driver is available for an
Atmel
® ARM7 microprocessor.
For ShortStack device development, you use the C or C++ programming
language. Alternatively, you can develop ShortStack devices using any
programming language supported by the host processor if you port the LonTalk
Compact API and the application framework generated by the LonTalk Interface
Developer utility to that language.
You use the Echelon LonTalk Interface Developer (LID) utility to create the
application framework. Your application uses the Echelon LonTalk Compact
Application
Serial I/O Driver
ShortStack
ISO/IEC 14908-1
Layers 2 – 6
ISO/IEC 14908-2 or 3
Layer 1 PHY
Smart Transceiver
Host Processor
Communications Channel
LonTalk API
ISO/IEC 14908-1
Layer 7