CC1200: Bit flips on first byte

Pawan Ghotikar

Part Number: CC1200

Hi,

In our project we observed that there is a bit flip while reading the received data. Strangely, it is the same bit which gets flipped.

For example,

1. if we send 0x00 0x54 then we receive 0x40 0x54

2. if we send 0x04 0x80 then we receive 0x44 0x80

Can someone assist?

-Pawan

over 6 years ago

0 TER over 6 years ago

TI__Guru**** 317180 points

Could you give the exact steps to recreate this on my side? You are not saying anything about which settings you are using, including sync word.

0 Pawan Ghotikar over 6 years ago in reply to TER

Expert 1140 points

TER,

I am trying to write for the third time because as I scroll to smart RF to find the exact settings, TI page refreshes and erases whatever I typed.

We have the following settings

169MHz, 500ksps 4-GFSK, std ETSI, fixed 12 bytes

Preamble count 0.5 byte, Sync word length 24bits, no sequence number added

Thanks,

Pawan

0 Pawan Ghotikar over 6 years ago in reply to Pawan Ghotikar

Expert 1140 points

Also, SYNC_CFG1 = 87

0 TER over 6 years ago in reply to Pawan Ghotikar

TI__Guru**** 317180 points

500 kbps uses zero IF meaning that > 4 byte preamble is needed. Have you tried with a longer preamble?

As for SmartRF Studio, you can save a config file that you can attach

0 TER over 6 years ago in reply to TER

TI__Guru**** 317180 points

Any feedback?

0 Pawan Ghotikar over 6 years ago in reply to TER

Expert 1140 points

I will be trying it this week. I was busy with something else. I will be updating as soon as I perform the suggested test.

-Pawan

0 Pawan Ghotikar over 6 years ago in reply to Pawan Ghotikar

Expert 1140 points

TER,

So we increased the preamble Count to 3 bytes and Sync Word length to 32 bits and the PER has enormously reduced. No bit flips.

Also, if you can suggest us the co-relation between the above two settings and why 0.5 preamble count doesn't work.

Thanks,

Pawan

Sub-1 GHz

Sub-1 GHz forum

CC1200: Bit flips on first byte