ANT Forum

Hi, i'm trying to make a point-to-point connection between a nRF24AP1 and the USB ANT Stick.

I'm sendind the packets to the nRF24AP1 to configure the channel, open it and than start to send a lots of data 0xAA, just to test the connection.

After that, i'm configuring the USB ANT Stick to make pair with the nRF24AP1, and when i open its channel as a receiver, i'm monitorating what packets are coming. And looking what's coming, the hexdecimal values, they are the ChannelEventFunc, and not the data that i'm trying to receive =/

What that mean? The data is 0xa4 0x03 0x40 0x00 0x40 0x28 0xchecksum

What's this 0x28 (message code) ?
And i'm receiving a lots of theses packets, intermittently.

Thanks a lot for the help.
Best regards,
Cauê      

Hi,

According to 'ANT Message Protocol and Usage' document, message code '0x28 = 40' indicates INVALID_MESSAGE.

Are you trying to send 0x40 message? This message is only sent by ANT.      

No, what i'm doing is:

I'm sending these packets to the USB ANT Stick:

0xa4014a00ef (reset)
0xa40342000000e5 (assignch as a receiver in channel 0)
0xa405510000000000f0 (setchid with wildcard)
0xa4014b00ee (open channel 0)

When i send each one of these messages, i receive a message back with the message ID = 0x40, data1 = 0x00, data2 = the corresponding message ID above, data3 = 0x00 (what's RESPONSE_NO_ERROR, right?), so i suppose that the USB ANT Stick is correctly configured.

At the same time, with the nRF24AP1 already configured and paired, it's been sending intermittently packets 0xAA.

What i'm doing is right?

So ... after a while the USB ANT Stick send a "search timeout" to my notebook, like if it is waiting for packets and nothing is coming. And after the "search timeout" it starts to send a lots of packets with message ID 0x40 and message code 0x28. Can you undestand? (I'm brazilian, so forgive me for the english mistakes)

Thanks,
Cauê      

Hi,

Do you have the rest of the channel parameters configured the same for both ANT devices; i.e. network key, RF channel frequency and channel period?

These parameters should be the same on both devices in order to establish communication between them.      

I'm not configuring the rest of the channel parameters because ANT said that these parameters have a default value, so, if you don't configure them, they will assume a certain value, correct?      

Hi,

Do you know what these default values are? If yes, are those values also used to configure the transmitting ANT node?

I believe the default values are the following:
- Network key: public network key
- RF channel frequency: 66 MHz
- Channel period: 4 Hz

However, it is recommended that you set these values on both sending and receiving sides so that communication is established.

When configuring an ANT channel, you need to first assign the channel then set the other parameters such as RF channel frequency, channel period...etc. The reason behind this is that when a channel is assigned those parameters; RF channel frequency, channel period...etc., will be reset.