AN2103 Freescale Semiconductor / Motorola, AN2103 Datasheet - Page 14

• Manufacturer Part Number: AN2103
• Description: Local Interconnect Network (LIN) Demonstration
• Manufacturer: Freescale Semiconductor / Motorola

14
Application Note
The Motorola API is entirely message based. The message identifiers
for a specific node are configured at compile time through header files.
The application accesses the data transmitted using the LIN_GetMsg()
and LIN_PutMsg() services. The application retrieves or transmits the
data associated with the identifier. (The address of a buffer that contains
the data to be transmitted or received and the message identifier are
passed to the driver, by the application). The drivers are easily used with
no additional tools and are linked with the application code.
The main difference of the LIN API is that it is signal based. The
application code does not access the entire message data, but only
specific signals. A signal consists of one or more bits of data. The drivers
provide services to access particular signals of varying lengths. (1 bit,
2-8bits and 9-16bits). In order to use the drivers an additional description
file is required that describes all the signals that are specific for a
particular node. This description file is then converted to header files (an
additional tool is required for this) and included with the application.
Every node on the network requires a separate description file that
contains its specific signals. This file is also used with the LINspector tool
for development and evaluation. The LIN API has provision to connect
to several hardware interfaces (more than one SCI).
The LIN Drivers are currently available for the HC05, HC08 and HC12
families of microcontrollers. Details of the HC08 implementation are
given below.
Note1: Figures exclude per message overhead
Note2: Motorola API/LIN API
Contact Motorola Software Systems for further information.
[e-mail]
Master
Slave
Node
Freescale Semiconductor, Inc.
For More Information On This Product,
20000
20000
Rate(bps)
LINBaud
Go to: www.freescale.com
4
4
frequency
MCU bus
<9%
<5%/6%
MCU load
23
20/21
(bytes)
RAM
1391
1071/689 <34/19
(bytes)
ROM
MOTOROLA
<34
(bytes)
Stack
AN2103