How to reduce the message send timeout in the Zstack

pratap yenubari

Expert 2305 points

Other Parts Discussed in Thread: CC2520

Hi,

I am working with Zstack-EXP5438-2.5.1 for WSN.i am using Experiment board EXP-msp430f5438 with CC2520 for the nodes.

In the sample example "GenericApp" ,the file GenericApp.h has a macro

// Send Message Timeout
#define GENERICAPP_SEND_MSG_TIMEOUT 120

I am not able to reduce the value less than 120.The moment I do,the association between the nodes fail.And the message "orphan response" flashes on the LCD screen.

Can somebody please suggest how to fix it.

thank you,

pratap y

over 11 years ago

0 pratap yenubari over 11 years ago

Expert 2305 points

And also which parameters should i look into for sending sensor data using the above mentioned ZStack-EXP5438-2.5.1 stack

0 KEERTHI G over 11 years ago in reply to pratap yenubari

Expert 2610 points

Why do you need to reduce the timeout below 120?

Is coordinator and end device both sends data?

Regards,

Keerthi G

0 pratap yenubari over 11 years ago in reply to KEERTHI G

Expert 2305 points

Hi.keerthi,
Yes both coordinator and end device both sends data.

Actually we are tar-getting a signal of up to 250hZ for buildings and bridges.

for us it is not necessary whether i reduce timeout below 120.i want to produce signal upto 250hz.

Can you plz help

0 pratap yenubari over 11 years ago in reply to KEERTHI G

Expert 2305 points

actually we are trying to build a WSN system by interfacing sensor data (acceleration). we are storing the adc values and sending the data with delay of 1ms. what is the relation between the delay in ADC and the transmission timeout if any to adjust the transmission.

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

Hi pratap,
Your question is similar to the discussion at e2e.ti.com/.../401453. You can refer to my replies there.

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

yes sir he is working with us only.and as per your suggestions we will be able to pull 250 hz easily for given 16kbps.

and also i want to use the full data payload of the frame(without security) which comes to around 100 bytes to transfer sensor values.

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

According to my experiences, it is OK to transmit data in this data rate.

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

I have come across the following link which says that we can reduce the message send timeout to 10ms.

e2e.ti.com/.../558951

can you help

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

In that discussion, there is no ADC reading involved and the message length is only 12 bytes. According to my experience, the message time out should be set to about 80 to 100ms if the message length is about 80 bytes.

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

sir,we are not able to go below 150ms for 1 byte or 80 bytes.
in the case of not using ADC,in that case also we are not able to crack below 150ms

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

If you don't change anything else but only set timeout to 100ms in GenericApp, you should be able to send "Hello World!" message in 100ms period.

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

sir,
we have tried by setting 100ms but we are not able to see the " hello world" message in end device.we are able to see the msg in the coordinator.

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

What is the polling rate of your end device?

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

we haven't set any polling rate for the end device.
where to set it and how it effect the result?

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

You can change the polling rate in f8wconfig.cfg. Just change "-DPOLL_RATE=1000" to "-DPOLL_RATE=100" which means change polling rate from 1000ms to 100ms. If the message is sent to ZED, it would be kept on its parent node and wait ZED to polling. The default polling rate is set to 1000 so it take 1000ms to get next message.

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

sir,
we changed " -DPOLL_RATE=1000" to "-DPOLL_RATE=100" but still we are not able to break the 150ms barrier for message sendout.
we have not changed any other parameter except for messagetimeout and DPOLL RATE.
are we supposed to change any other paremeters

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

According to my experiences, message timeout can be set as low as 80ms if you send message from ZED to ZC and message length is less than 80 bytes. If the message is sent from ZC to ZED, it is reasonable that message timeout can not be less than 150ms. You can decrease the polling rate to 50ms and see if you can get some improvement.

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

Sir,
We have successfully reduced the message timeout to 5ms.We have removed the delay for the settling time of reference voltage and ran the code with reduced message timeout of upto 5ms and the data is being transmitted.

but this data transmission is occurring only in case of end device and coordinator,and only end device is sending the data.we have not used any router.but when are introducing the router node in the network the data is getting corrupted and we are not able to reproduce the expected wave form.
can you suggest any help.
thank you

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

When you add router into Zigbee network, there might be some message routing delay. If you can make ZED to send message every 5 ms in a no ZR system, I would suggest you to triple the message timeout in a system with ZR.

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

Sir,

We tripled the message timeout in a system with ZR and kept it at 15ms. We are able to see the waveform although it is still distorted but still it can be worked out.

There is one other problem though as we increased the timeout value the number of bytes sent per second is reduced to 66 bytes per second and with this value we are only able to reconstruct the wave up to 20Hz.

We tried to increase the number of bytes sent in one packet and increased it from 1 to 5 and the range increased but now we get five frequency peaks after fft of time domain data and correct frequency peak is dominant only up to 20 Hz.

Can you suggest something for this problem.

We only want to use router to transfer the end device data to coordinator and it should not do any processing. So is there something that can be done to solve our problem.

Thank you

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

When you send data every 15ms, how many bytes is in a sending packet? Just one byte or many bytes?

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

Sir,
i am sending one byte only.

i have tried with multi bytes also but same result

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

Form my point of view, you can collect data in an array (for example, 80 bytes in this array) and send this array every 100ms. In this way, you will have 800 samples per second.

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

Sir,
We have tried using 80 bytes .but are not able to reproduce the required sine wave for a given sine input.
we want to ask how the 80 samples(800 samples /second) will be distributed over a period of 100ms.
becoz they need to be distributed uniformly for recreating a periodic sine wave.

what we think the 80 bytes are being produced in the first 5-10 ms as per sampling frequency,therefore the wave is not reconstructed properly

0 YiKai Chen over 11 years ago in reply to pratap yenubari

Guru 735695 points

From my point of view, 800 bytes per seconds is almost the fast data rate you can send from ZED to ZC with ZR in the network. To reconstruct sine wave properly, you have to make 80 bytes sampled smoothly in 100 ms duration and send every 100ms. On the ZC, you can plot a points on sine wave every 1.25ms and it should be good enough form application point of view.

0 pratap yenubari over 11 years ago in reply to YiKai Chen

Expert 2305 points

SIr,

For any sampling frequency if i take timeout value to be 100ms then sampling should be finished as early as possible,probably in first 30ms other wise the association of nodes fail.

so if you say plot points on sine wave every 1.25ms,how is this justified???
we have checked this practically.

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How to reduce the message send timeout in the Zstack