82C900 Datasheet, PDF (7/29 Pages) Infineon Technologies AG – Standalone TwinCAN Controller

82C900
Preliminary
Application Fields
The Standalone TwinCAN device 82C900 can be used in application requiring one or
two independent CAN nodes. The built-in FIFO and gateway features minimize the CPU
load for the message handling and lead to an improved real-time behavior. The access
to the internal registers can be handled via a parallel or a serial interface, adapted to a
large variety of applications. The interface selection is done via the two MODE pins,
which can be directly connected to the supply voltage or via pull-up/down resistors (of
about 10-47 kOhm). In all modes, the clock generation can be controlled either by the
82C900 device or by the system it is connected to.
Connection to a Host Device via the Parallel Interface
The 82C900 can be connected to a host device via a parallel 8 bit multiplexed interface.
Therefore, pin MODE0 has to be 0, whereas pin MODE1 selects, whether an Infineon-
(Intel-) compatible or an Motorola-compatible protocol is handled. In this mode, the
device can be easily used to extend the CAN capability of a system. The internal
registers can be accessed in pages of 256 bytes per page. An additional RDY output
indicates when the device is ready to be accessed. This signal can be used to detect an
overload situation of the CAN device (too many host accesses to the TwinCAN module).
One interrupt output line (OUT1) is always available, a second one (OUT0) can be used
as clockout pin or as another interrupt output.
CAN Bus A
CAN Bus B
Transceiver
Transceiver
RXDCA,
TXDCA
RXDCB,
TXDCB
82C900
TwinCAN Module
Clock Control
Parallel Interface
Interrupt
Control
AD7..0
CTRL3..0 RDY
OUTx
Host
Figure 2 Host Connection via the Parallel Interface
Data Sheet
7
V 1.0D3, 2001-03