Rpi4 and CN301 usage

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Tokio

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Dec 8, 2020, 9:01:40 PM12/8/20
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Johan,

I would like to confirm the CN301 usage for NO Controller Mode of piHPSDR:

In SSB, I would like to use an external PTT to transmit. In CN301 configuration above, there are
ptt_out: pin 3
RPI-Keyer-dash(pihpsdr): pin 5
RPI-Keyer-dot(pihpsdr): pin 6
push-to-talk: pin 13
key input: pin 14.

(1) When key input(pin 14) grounded, I can send in SSB, and ptt_out turns to active(3.3 V). ptt_out can be used for the PTT of a linear amplifier.

(2) However there is a delay from TX to RX(this is a break in delay of CW in piHPSDR). When MOX clicked, TX to RX is quite smooth.

(3) push-to-talk(pin 13) seems no working.

Is there a good way to PTT by an external input for SSB?

73,
Tokio
ja1cca
pihpsdr panel.PNG
pihpsdrinterface config.PNG

pa3gsb

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Dec 9, 2020, 6:56:23 AM12/9/20
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Tokio

Your config is wrong.


FYI:
pihpsdr is using wiring pi and numbers.

Hope this helps.

73 Johan
PA3GSB

Op woensdag 9 december 2020 om 03:01:40 UTC+1 schreef Tokio:

Tokio

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Dec 9, 2020, 8:01:50 AM12/9/20
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Johan,

Thank you very much for your message including Raspberry GPIO info.

I corrected piHPSDR GPIO configuration as attached.
The push-to-talk pin 13 starts to work. However it is very sensitive and unstable in a manner that when I connect a wire to pin 13, and the other side of this wire is open, not grounded, but piHPSDR goes to TX.  This doesn't always happen, but frequently.
In addition, when pin 13 is grounded, piHPSDR goes to TX. But, I can use MOX, then RX with pin13 grounded.
Is there a need to pull-up this pin 13?

73,
Tokio
ja1cca



2020年12月9日水曜日 20:56:23 UTC+9 pa3gsb:
GPIO_piHPSDR.PNG

Radioberry

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Dec 9, 2020, 8:49:18 AM12/9/20
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Tokio

R307 and R308 can be placed. Without these resistors only the weak internal FPGA resisitor is present as configured in the pins file:

set_instance_assignment -name WEAK_PULL_UP_RESISTOR ON -to io_phone_tip
set_instance_assignment -name WEAK_PULL_UP_RESISTOR ON -to io_ptt_out
set_instance_assignment -name WEAK_PULL_UP_RESISTOR ON -to io_cwl
set_instance_assignment -name WEAK_PULL_UP_RESISTOR ON -to io_cwr

With resistors in place it will be beter.

73 Johan
PA3GSB

Op woensdag 9 december 2020 om 14:01:50 UTC+1 schreef Tokio:

Tokio

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Dec 9, 2020, 9:33:12 PM12/9/20
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Johan,

Thank you for your confirmation.

I put a pull-up resistor 10K ohms for R307. Since I have only one 0603 smd of 10K ohms at the moment.
I'll buy 0603 10K ohms tomorrow for R308.

Now, pin 13 works fine. With this, I can make use of an external PTT switch. And I also confirmed the function of ptt_out (pin 3) to activate my 100 W amplifier. I use MOSFET and MOSFET Relay to isolate the ptt output.

73,
Tokio
ja1cca
2020年12月9日水曜日 22:49:18 UTC+9 Radioberry:
CN301.jpeg
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