Specifications

CAN driver blocks for the CAN-AC2 (ISA) with Intel 82527 CAN-Controller
4-21
a model per physical CAN board cannot exceed 200 (restriction of the
firmware’s dynamic object mode). The number of elements defined here, define
at the same time the number of output ports of the block. The block icon
displays the selected identifier at each output port. Each output port will
output the data frame being retrieved along with the CAN-message. The signal
leaving each output port is a scalar of type double representing the maximum
size of 8 bytes of a CAN-message’s data frame.
Output port options — The fourth control (popup menu) lets you define which
type of retrieved data is output at each output port. Three different types of
data can be output, which are data frame, status and timestamp. The status
information is of type double and is identical to the return value of function
CANPC_read_rcv_data(…) described in the Softing user manual. Refer to the
manual for more information. The timestamp information is of type double and
outputs the latest time at which a CAN message with the corresponding
identifier has been received. This time information in seconds (with a
resolution of 1 microsecond) can be used to implement timeout-logic within
your model.
The popup menu lets you select which output information is output at each
output port of the block. If “Data” is selected each output port signal is a scalar
only. If “Data – Status” is selected each output port signal is a vector with two
elements, where the first element contains the data frame and the second
element the status information. If “Data – Status – Timestamp” is selected
each output port signal is a vector with three elements, where the first element
contains the data frame, the second element the status information, and the
third element the timestamp.
Generate interrupts — The fifth control (check box) lets you define if the CAN
messages defined in this instance of the block will initiate an interrupt from
the CAN board each time they are received. If checked this allows driving the
model (target application) execution controlled by CAN messages.
Sample time — The sixth control (edit field) defines the sample time at which
the Send block is executed during a model (target application) run.
You can use as many instances of the Receive block in the model as needed. For
example by using two instances of the block with different sample times, CAN
messages can be retrieved at different rates. Or you can use multiple instances
to structure your model more efficiently.