In some CAN bus applications, the exact period of CAN bus message generation is important. By simply generating these messages from a PC for higher frequencies, this precise timing is difficult to achieve. The older USB2CAN converter offered this data generation feature as part of an alternative firmware. The USB2CAN Triple and Combo converters also get this feature as part of the base firmware from version 1.24.
The CAN message generation period is configurable with a resolution of 100 microseconds, settings can be made for any of the 3 CANs and it is also possible to generate data synchronously on all 3 CAN ports. Within this version, automatic checksums and counters according to SAE J1939 (SPN 4207, SPN 4975, SPN 3188 and SPN 3690) are also available which are calculated for each generated message. Any additional checks and counters for other CAN protocols (even non-standard ones) can be added free of charge to future firmware versions after the delivery of the relevant documentation.
The message data can thus be updated if necessary, the actual generation with the exact period is provided by the converter. The user application can thus write new data to the corresponding HW sync buffer. The converter generates the message and the current data according to the set period on the CAN bus. If set, it calculates the current value of the checksum and, if applicable, the counter before each message is sent to the bus.
