# Zero value of rssi in promisc\_callback userdata

**URL:** https://forum.amebaiot.com/t/zero-value-of-rssi-in-promisc-callback-userdata/908
**Category:** SDK
**Tags:** evb-bw16
**Created:** [November 16, 2021, 2:23am UTC](https://forum.amebaiot.com/t/zero-value-of-rssi-in-promisc-callback-userdata/908 "2021-11-16T02:23:33Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![Jeffery](https://avatars.discourse-cdn.com/v4/letter/j/c0e974/32.png) [@Jeffery](https://forum.amebaiot.com/u/Jeffery)
#### Post date: [November 16, 2021, 2:23am UTC](https://forum.amebaiot.com/t/zero-value-of-rssi-in-promisc-callback-userdata/908/1 "2021-11-16T02:23:33Z")

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Hello,  
The problem I met is zero value of rssi in some of promisc\_callback user data.

 ![41UL69QUQC6HT55RO}9`~@X](https://us1.discourse-cdn.com/flex016/uploads/ameba/original/1X/ab8cab1a94ce6eb2f5e69e88390a485558ad6a43.png)

the rssi field in userdata

 ![FPX5V15Y}`@7HE~W~OS1](https://us1.discourse-cdn.com/flex016/uploads/ameba/original/1X/641bf7006f26fde9a8a2f099d3aa459a93ecec00.png)  
To be detailed, when I set the module in promisc mode, and use AT command ATWM to capture the packet in the air. I find some of captured packet (rssi field in userdata of promisc\_callback) returns zero, while most of cases, the value is valid in range of -128 ~ -1. So, I wonder why it returns zero, what does it mean?

BTW: The ambd\_sdk version is master of github. The module is BW16 hardware.

Thanks,  
Jeff

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### Author: ![M-ichae-l](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.amebaiot.com/m-ichae-l/32/33_2.png) [@M-ichae-l](https://forum.amebaiot.com/u/M-ichae-l)
#### Post date: [November 16, 2021, 10:36am UTC](https://forum.amebaiot.com/t/zero-value-of-rssi-in-promisc-callback-userdata/908/2 "2021-11-16T10:36:34Z")

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Thank you @Jeffery . We are checking this issue. Any example from the SDK, you are running? So I can re-produce the issue.

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### Author: ![Jeffery](https://avatars.discourse-cdn.com/v4/letter/j/c0e974/32.png) [@Jeffery](https://forum.amebaiot.com/u/Jeffery)
#### Post date: [November 17, 2021, 8:18am UTC](https://forum.amebaiot.com/t/zero-value-of-rssi-in-promisc-callback-userdata/908/3 "2021-11-17T08:18:18Z")

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Hello,  
I’m testing the  
_static void promisc\_test(int duration, unsigned char len\_used)_ in wifi\_promisc.c. To figure out the captured package, I add some logging printf in this function. It will print the rssi value.  
This function is called in fATWM, which could be triggered by AT command ATWM.

The code is master branch of github [GitHub - ambiot/ambd\_sdk: SDK for AmebaD](https://github.com/ambiot/ambd_sdk)

Thanks,  
Jeff

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### Author: ![daphwl](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.amebaiot.com/daphwl/32/756_2.png) [@daphwl](https://forum.amebaiot.com/u/daphwl)
#### Post date: [December 16, 2021, 7:05am UTC](https://forum.amebaiot.com/t/zero-value-of-rssi-in-promisc-callback-userdata/908/4 "2021-12-16T07:05:43Z")

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Hi @Jeffery, you can try to use the code in the release branch of Github: [GitHub - ambiot/ambd\_sdk at release](https://github.com/ambiot/ambd_sdk/tree/release)