Data Sent To (Rpdo) And From (Tpdo) Module - ECM appsCAN Module Instruction Manual

Data Sent to (RPDO) and from (TPDO) Module

Data sent to (i.e. commands) appsCAN modules is packaged as RPDOs (Receive Process
Data Object). Data sent from appsCAN modules is packaged as TPDOs (Transmit Process
Data Object). Each RPDO and TPDO contains two parameters and each module can receive
up to four RPDOs and send up to four TPDOs. All selected TPDOs will be sent at the
broadcast rate. For example, if the broadcast rate is 5 ms and four TPDOs were selected to
be sent, then eight pieces of data would be transmitted every 5 ms. To avoid slowing down
the effective data rate on the CAN bus, select the number of TPDOs to be sent and the
broadcast rate sparingly. For the case of multiple modules sending multiple TPDOs on the
same CAN bus, the minimum (i.e. fastest) broadcast rate is given by:
Minimum Broadcast rate (ms) = The total number of TPDOs for all modules x 0.3125
For example, if there are eight modules, each sending two TPDOs, the minimum broadcast
rate is 5 ms.
RPDO data is sent to the module when the "Send" button is pressed. However, if the
"Activation of RPDOs" is set up to be in SYNC mode, a SYNC command must be sent to the
module for it to act on the RPDOs sent.
The data sent or received from appsCAN modules is selected in the "Data" area of the
Configuration Tool. Click in the "Data View" area to select TPDOs or RPDOs. Activate the
number of TPDOs and RPDOs by clicking in its box to put in a check mark. Select the data
contained in each TPDO and RPDO using the pull-down windows. The list of available
parameters for the appsCAN module is given in Table 2.
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