P82C150AFT Philips Semiconductors, P82C150AFT Datasheet - Page 14

• Manufacturer Part Number: P82C150AFT
• Description: CAN Serial Linked I/O device SLIO with digital and analog port functions
• Manufacturer: Philips Semiconductors

Philips Semiconductors
7.3
The P82C150 meets the CAN protocol specification
version 2.0 A and B (passive) with restricted bit timing
because of the on-chip RC-oscillator and the automatic bit
rate detection.
In a system with P82C150 nodes there must be at least
one conventional crystal-driven CAN controller (host node)
which is compatible to the CAN specification V1.2 or later
to control P82C150 nodes. Host nodes compatible to CAN
specification V1.1 can also be used provided that the
P82C150 nodes are powered by a high-accuracy power
supply or they are in external oscillator mode (refer to
Section 11.3).
Each time a P82C150 node receives a Data Frame, it
initiates the transmission of a Data Frame containing four
bits status information, the register address (previously
received) and the current contents of the addressed
register (exception: see Section 7.3.3.1). This enables the
Table 5 Message types and format
Note
1. DLC = Data Length Code; DIR = LSB of Identifier (see Section 7.3.1).
Table 6 Standard Format Identifier bits ID.10 to ID.0
1 = recessive; 0 = dominant
Table 7 Description of the Standard Format Identifier bits
1996 Jun 19
Data Frame
Remote Frame
Error Frame
Overload Frame
ID.5 to ID.3 P2 to P0
ID.10
CAN Serial Linked I/O device (SLIO) with
digital and analog port functions
0
ID.8
ID.0
BIT
FRAME
CAN functions
ID.9
1
P3
DIR
RTR
SYMBOL
yes (DLC = 3; DIR = 1)
no
yes
yes (only as a response)
ID.8
P3
TRANSMISSION BY 82C150
Programmable identifier bits read from Port pins P3 to P0 during reset. The input levels
on P3 to P0, for example set by resistors to V
latch with the falling edge of the RST input signal. They represent the variable part of
the Identifier, while the remaining bits are fixed (mask-programmed), P3 to P0 can be
used as I/O ports after reset.
DIR = 1 for transmission of Data Frames to the host. It must be set to a logic 1 in
Remote Frames and to a logic 0 in Data Frames received from the host.
Remote Transmission Request bit.
ID.7
1
ID.6
0
IDENTIFIER
ID.5
P2
14
host node to verify that the addressed register has
correctly been written in case of writeable registers, and to
read the contents in case of readable registers.
7.3.1
Data and Remote Frames to be processed by the
P82C150 are of Standard Format with 11 Identifier bits
ID.10 to ID.0. Frames with extended Identifier (CAN
specification version 2.0 B) are ignored.
The way of identifier programming is based on two facts:
ID.4
P1
Each P82C150 operates with only two Identifiers
distinguished by the LSB (see Tables 5, 6 and 7).
The identifier with the higher priority is used for Data
Frame reception. An extra Identifier is used for
calibration purposes.
There can be maximum sixteen P82C150 circuits in one
network.
DESCRIPTION
CAN I
yes (DLC = 3; DIR = 0; calibration message
with DLC = 2 to 8 allowed, see Section 7.3.10)
yes (DLC = 3; DIR = 1)
yes
yes
ID.3
P0
SS
DENTIFIER
or to V
RECEPTION AT 82C150
ID.2
1
DD
, are latched in the Identifier
ID.1
0
Preliminary specification
ID.0
DIR
P82C150
RTR