LAUNCHXL-CC1310: TX echo example

Joselito Go

Part Number: LAUNCHXL-CC1310
Other Parts Discussed in Thread: CC1310

Hi Experts,

Good day.

Would you help to obtain an understanding of:

Q1: I'm studying the example "rfEchoTx_CC1310_LAUNCHXL_nortos_ccs", So I can't understand the point of one "if-snippent" in the example - it is on the picture attached to this letter.

Q2: Would U explain the point of the field "pastTrig" of the structure

struct __RFC_STRUCT rfc_CMD_PROP_TX_ADV_s {

.....

struct {
      uint8_t triggerType:4;            //!<        The type of trigger
      uint8_t bEnaCmd:1;                //!< \brief 0: No alternative trigger command<br>
                                        //!<        1: CMD_TRIGGER can be used as an alternative trigger
      uint8_t triggerNo:2;              //!<        The trigger number of the CMD_TRIGGER command that triggers this action
      uint8_t pastTrig:1;               //!< \brief 0: A trigger in the past is never triggered, or for the start of commands, give an error<br>
                                        //!<        1: A trigger in the past is triggered as soon as possible
   } startTrigger (endTrigger);

....

I can't understand what means :

0: A trigger in the past is never triggered, or for the start of commands, give an error<br>
1: A trigger in the past is triggered as soon as possible

what is the behavior/point? Would you explain it more widely and in detail

Please advise.

Regards,

Josel

over 2 years ago

0 Siri over 2 years ago

TI__Guru* 85901 points

There are no pictures attached to this post, so please specify what you are asking in Q1.

For the past trigger, assume the following.

At time t_n, you are issuing TX command with a start time at time t_n+1

In this case, the pastTrig setting is don’t care, and the packet will be sent at t_n+1

However, if you have a case where the start time is set to t_n+1, but you are not issuing the command before time t_n+2, then the pastTrig will affect what is happening.

If pastTrig = 0, the packet will not be transmitted, and the TX command will return an error (this is because you called the command at t_n+2, and wanted the packet to be sent at t_n+1

If pastTrig = 1, the packet will be sent as soon as possible, in this case, at time t_n+2

_Siri

0 Joselito Go over 2 years ago in reply to Siri

TI__Expert 5890 points

Hi Siri,

My apology for that. below is the image

Regards,

Josel

0 Siri over 2 years ago in reply to Joselito Go

TI__Guru* 85901 points

In the example, the TX command is chained with an RX command.

The TX command will always run and result in a RF_EventCmdDone interrupt.

The RX command can generate 3 different interrupts:

RF_EventCmdDone
RF_EventLastCmdDone
RF_EventRxEntryDone

1 and 2 will always happen, while 3 will only happen if a packet is received.

Assume you get the callback and RF_EventRxEntryDone is asserted (packet is received). The code will then set bRxSuccess = true; set the proper LEDs and return (will not check the next else if)

You will then have the callback again when RX is finished (RF_EventRxEntryDone).

the RF_EventRxEntryDone is already cleared on the previous interrupt, so the

else if((e & RF_EventLastCmdDone) && !(e & RF_EventRxEntryDone)) is true.

It is not necessary to figure out if a packet was actually received (bRxSuccess) or if the RF_EventRxEntryDone never happened and the RF_EventLastCmdDone happened due to a timeout.

Siri

Sub-1 GHz

Sub-1 GHz forum

LAUNCHXL-CC1310: TX echo example