[Fixed] DMR Rx dropout

VK3KYY
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Location: Melbourne, Australia

Re: DMR Rx Dropout

Post by VK3KYY » Thu Sep 29, 2022 1:39 am

Anyone with the DMR Rx dropout

Can you change to using this version

https://opengd77.com/downloads/MDUV380/ ... 01196e4f59

Colin has discovered a clash between various parts of the firmware accessing the C6000 DMR chip, which is probably what has been causing a lot of the problems.

I have also changed all the interrupt signal priorities to make sure the CPU can instantly respond to the C6000 when there is a DMR Timeslot synchronisation trigger.

And I have also changed the ADC processing which samples the volume control and battery and VOX, so this is handled by Direct Memory Access in the processor, rather than software ADC sampling
Its possible that the ADC sample rate will need to be adjusted, as I reduced it from 1000 samples per second, which was much more than was necessary to around 50 samples per second. But possibly we should use 100 samples per second for the volume control.

Note. The volume control in this radio is unfortunately not direct hardware, and the CPU has to handle the changes to volume control

Also battery voltage display averaging may also need to be adjusted, and currently the displayed battery voltage will not change as quickly in response to changes to supply / battery voltage changes

S58SMS
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Joined: Mon Dec 20, 2021 8:00 am

Re: DMR Rx Dropout

Post by S58SMS » Thu Sep 29, 2022 7:18 am

i will try it later today and report.

VK3KYY
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Location: Melbourne, Australia

Re: DMR Rx Dropout

Post by VK3KYY » Thu Sep 29, 2022 7:31 am

S58SMS wrote:
Thu Sep 29, 2022 7:18 am
i will try it later today and report.
Thanks

EU1AEQ
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Joined: Sat Jan 30, 2021 7:25 pm

Re: DMR Rx Dropout

Post by EU1AEQ » Thu Sep 29, 2022 8:54 am

Hello.
1.The 96 MHz version worked well.
2.Installed version Sep 29, 2022 - works for 3 hours, there are no errors yet.
3. What processor frequency is used in version Sep 29, 2022?

VK3KYY
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Re: DMR Rx Dropout

Post by VK3KYY » Thu Sep 29, 2022 10:08 am

EU1AEQ wrote:
Thu Sep 29, 2022 8:54 am
Hello.
1.The 96 MHz version worked well.
2.Installed version Sep 29, 2022 - works for 3 hours, there are no errors yet.
3. What processor frequency is used in version Sep 29, 2022?
Latest version is 96Mhz, becuase the CPU takes less current at 96Mhz and its not necessary to use the full processing power of the CPU

On the GD77, I think the default CPU clock frequency is even lower, but lower CPU clock frequencies cause display problems on the UV380 / RT3S

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DG1GMY
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Location: Southern Germany

Re: DMR Rx Dropout

Post by DG1GMY » Fri Sep 30, 2022 7:45 am

No RX dropouts since! The battery life also seems to have improved with this version.

VK3KYY
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Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia

Re: DMR Rx Dropout

Post by VK3KYY » Fri Sep 30, 2022 8:03 am

DG1GMY wrote:
Fri Sep 30, 2022 7:45 am
No RX dropouts since! The battery life also seems to have improved with this version.
Thanks

I've found some other problems with the processor clock speed setup, and have probably found the main cause of the dropout, which was not actually the clock speed.

However it needs more testing before I can post anything.

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WY7JT
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Re: DMR Rx Dropout

Post by WY7JT » Fri Sep 30, 2022 9:00 pm

I've been using the 96 MHz version, and none of those cyclical drop outs. But over a couple days I've heard stations go to that underwater sound like we had in the early days of the GD-77 firmware, but only a couple times.

VK3KYY
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Location: Melbourne, Australia

Re: DMR Rx Dropout

Post by VK3KYY » Fri Sep 30, 2022 9:06 pm

WY7JT wrote:
Fri Sep 30, 2022 9:00 pm
I've been using the 96 MHz version, and none of those cyclical drop outs. But over a couple days I've heard stations go to that underwater sound like we had in the early days of the GD-77 firmware, but only a couple times.
Thanks

We have discovered multiple problems related to the processor clock frequency, the flash memory latency settings, the Serial Peripheral Interface speed.
All of which affect DMR RX and Tx

Its going to take some time to resolve these problems.

ik2tif
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Joined: Fri Aug 26, 2022 12:09 pm

Re: DMR Rx Dropout

Post by ik2tif » Sat Oct 01, 2022 4:25 pm

Good evening,

I have installed the 96mhz version for 2 days and I have no problem of drop, bad modulation or low signal.
Great for my RT3S, everything is fine for me.
Thanks to the whole team for the great job

73 Fabio

IK2TIF

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