Transmit FLEXRAY Frame with the right payload length

Discussion created by Richard DE MIRANDA on May 23, 2012
Latest reply on May 24, 2012 by Richard DE MIRANDA



I'm using an MCU 16-bit MC9S12XF512MLM. I have two Freescale developement tool card with this one. I use the example give by freescale to communicate between my two nodes.


I have donne some work based on this example but I still have a problem. I can not understand the real purpose of the variable "Payload length" :


const Fr_transmit_buffer_config_type Fr_tx_buffer_slot_10_cfg ={   10,                           // Transmit frame ID   0x1E3,                        // Header CRC   16, // Payload length   FR_SINGLE_TRANSMIT_BUFFER,   // Transmit MB buffering   FR_STATE_TRANSMISSION_MODE,  // Transmission mode   FR_IMMEDIATE_COMMIT_MODE,    // Transmission commit mode   FR_CHANNEL_AB,               // Transmit channels   FALSE,                       // Payload preamble   FALSE,                       // Transmit cycle counter filter enable   0,                           // Transmit cycle counter filter value   0,                           // Transmit cycle counter filter mask   FALSE,                       // Transmit MB interrupt enable   FALSE                        // Used only for double buffer};


I think, this variable is referenced by the "G_PAYLOAD_LENGTH_STATIC" in the structure of the Flexray Configuration.


When I want to change the value of the Payload Length ine my frame, it doesn't work... I don't know why...


For example, If I want to have a frame which a Payload Length of 34, how I can do that?


Thanks in advance,