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May 24, 2017, 01:50 PM
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If you're lucky it won't be damaged, an open circuit is less risky than a short circuit. No easy way to be sure but check your range.
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May 24, 2017, 01:53 PM
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Thread OP
Quote:
Originally Posted by Wayno Complaino
Gonna have a fiddle with the Orange 1W RX now.

There is only Ground, TX and RX available on pins so the question is:

Do I power it with the main input (6.5-12V) and then try connecting the FTDI with just the three Gn, TX, RX.

or

Is there a way of installing the firmware with a USBASP directly to the chip?
When programming the module should always be powered normally.

1) if using the serial port, you'll need RX, TX, GND but also the DTR signal. It's theoretically possible to do it without DTR by powering at a specific moment during the programming sequence, but it's quite difficult.

2) USBASP will work too, just remember that it will erase the bootloader. I'd propose to save your bootloader before programming the firmware with USBASP, so you can reinstall the bootloader if you need it later on.
May 24, 2017, 02:43 PM
Registered User
Quote:
Originally Posted by flipflap
If you're lucky it won't be damaged, an open circuit is less risky than a short circuit. No easy way to be sure but check your range.
Ok, I'm going to try it, and I'll tell you the result.

On the other hand, I think that PIXHAWK does not interpret RSSI correctly, which is the correct way to connect:

- RSSI wire from orange to SBUS (signal cable only)

- RSSI wire and GND from orange to SBUS

- RSSI wire and GND from orange to filter and RSSI and GND from filter to SBUS

And my current setup:

- RSSI wire and GND from orange to filter and only RSSI from filter to SBUS

I've never gotten an accurate reading.

Thanks!!
May 24, 2017, 02:54 PM
Fixed wings can be Drones too!
Wayno Complaino's Avatar
Quote:
Originally Posted by flipflap
When programming the module should always be powered normally.

1) if using the serial port, you'll need RX, TX, GND but also the DTR signal. It's theoretically possible to do it without DTR by powering at a specific moment during the programming sequence, but it's quite difficult.

2) USBASP will work too, just remember that it will erase the bootloader. I'd propose to save your bootloader before programming the firmware with USBASP, so you can reinstall the bootloader if you need it later on.
Looks like DTR is grounded directly unlike the TX module that has a pull down resistor. My knowledge is limited so excuse the questions.....

Can i solder directly to the chip Vcc, Gnd, Tx, Rx and DTR in order to flash? My soldering skills are up to the job but i dont wanna do it if you know it wont work.

Regarding USBASP. Its been an age since i last used it, just got it installed again (a faff on windows 10). USBASP shows up in device manager and i was hoping it showed up in ULRS CC, but it doesnt. Also, i have no clue how to save a bootloader already on the chip. Will do a bit of research but if there is an easy answer i'm all ears. Ta.
May 24, 2017, 04:28 PM
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Quote:
Originally Posted by waka_marbella
Ok, I'm going to try it, and I'll tell you the result.

On the other hand, I think that PIXHAWK does not interpret RSSI correctly, which is the correct way to connect:

- RSSI wire from orange to SBUS (signal cable only)

- RSSI wire and GND from orange to SBUS

- RSSI wire and GND from orange to filter and RSSI and GND from filter to SBUS

And my current setup:

- RSSI wire and GND from orange to filter and only RSSI from filter to SBUS

I've never gotten an accurate reading.

Thanks!!
RSSI should be connected to one of the analog inputs of the Pixhawk, not to SBUS pin :

http://ardupilot.org/copter/docs/com...ndication.html

For now a filter is required (capacitor + resistor), but soon (end of the month) you'll be good with nothing specific for the RSSI : it will be transmitted through one of the RC channels.
May 24, 2017, 04:33 PM
Registered User
Thread OP
Quote:
Originally Posted by Wayno Complaino
Looks like DTR is grounded directly unlike the TX module that has a pull down resistor. My knowledge is limited so excuse the questions.....

Can i solder directly to the chip Vcc, Gnd, Tx, Rx and DTR in order to flash? My soldering skills are up to the job but i dont wanna do it if you know it wont work.

Regarding USBASP. Its been an age since i last used it, just got it installed again (a faff on windows 10). USBASP shows up in device manager and i was hoping it showed up in ULRS CC, but it doesnt. Also, i have no clue how to save a bootloader already on the chip. Will do a bit of research but if there is an easy answer i'm all ears. Ta.
Unfortunately no easy answer for USBASP... If you don't mind I'll let you do some research on google first. (First learn how to read the chip content and save it to a file.)

Regarding serial flashing, GND, VCC, TX, RX are OK, but DTR must be connected through a capacitor. It should be already on the PCB, something like this :

May 24, 2017, 05:01 PM
RC fanatic
Quote:
Originally Posted by flipflap
RSSI should be connected to one of the analog inputs of the Pixhawk, not to SBUS pin :

http://ardupilot.org/copter/docs/com...ndication.html

For now a filter is required (capacitor + resistor), but soon (end of the month) you'll be good with nothing specific for the RSSI : it will be transmitted through one of the RC channels.
Flip - your first statement is not entirely accurate. The servo connector labelled SBUS, is not in fact SBUS input on the pixhawk, but was originally designed as an SBUS output. You can however configure a parameter to turn this SBUS port into the RSSI analog input. It is 3.3v based input though and so a divider is required to reduce the 5v based output from the ULRS Mini boards.

It is mentioned here: http://ardupilot.org/copter/docs/com...-overview.html search for "Virtual Pin 103: RSSI"

The parameters:
BRD_SBUS_OUT - must be set to 0 (to disable SBUS output)
RSSI_TYPE - must be set to 1 for "Analog pin"
RSSI_ANA_PIN - must be set to 103 for that SB (SBUS out) port
There are also:
RSSI_PIN_LOW and RSSI_PIN_HIGH for low/high voltage readings on that input. On Pixhawk, PIN_HIGH would normally be 3.3. - for APM, would normally be 5.0

With the next release of ULRS, as you say, we will be able to select a channel where the RSSI value will be represented in the PWM value presented there. To have Arducopter use this we would use the parameters as follows:

RSSI_TYPE - must be set to 2 (for RCChannelPwmValue)
RSSI_CHANNEL - set to the channel number containing the PWM value
RSSI_CHAN_LOW - set to the PWM value representing low RSSI
RSSI_CHAN_HIGH - set to the PWM value representing high RSSI
Last edited by athertop; May 24, 2017 at 05:23 PM.
May 24, 2017, 09:28 PM
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007trains's Avatar
Quote:
Originally Posted by Wayno Complaino
Regarding USBASP. Its been an age since i last used it, just got it installed again (a faff on windows 10). USBASP shows up in device manager and i was hoping it showed up in ULRS CC, but it doesnt. Also, i have no clue how to save a bootloader already on the chip. Will do a bit of research but if there is an easy answer i'm all ears. Ta.
Unfortunately USBASP won't appear as a standard com port, when i use USBASP in my arduino projects it seems to do a search for a USBASP device so it probably needs some software adaptation in order to use it with ULRS CC
May 24, 2017, 10:25 PM
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Thread OP
Quote:
Originally Posted by athertop
Flip - your first statement is not entirely accurate. The servo connector labelled SBUS, is not in fact SBUS input on the pixhawk, but was originally designed as an SBUS output. You can however configure a parameter to turn this SBUS port into the RSSI analog input. It is 3.3v based input though and so a divider is required to reduce the 5v based output from the ULRS Mini boards.

It is mentioned here: http://ardupilot.org/copter/docs/com...-overview.html search for "Virtual Pin 103: RSSI"

The parameters:
BRD_SBUS_OUT - must be set to 0 (to disable SBUS output)
RSSI_TYPE - must be set to 1 for "Analog pin"
RSSI_ANA_PIN - must be set to 103 for that SB (SBUS out) port
There are also:
RSSI_PIN_LOW and RSSI_PIN_HIGH for low/high voltage readings on that input. On Pixhawk, PIN_HIGH would normally be 3.3. - for APM, would normally be 5.0

With the next release of ULRS, as you say, we will be able to select a channel where the RSSI value will be represented in the PWM value presented there. To have Arducopter use this we would use the parameters as follows:

RSSI_TYPE - must be set to 2 (for RCChannelPwmValue)
RSSI_CHANNEL - set to the channel number containing the PWM value
RSSI_CHAN_LOW - set to the PWM value representing low RSSI
RSSI_CHAN_HIGH - set to the PWM value representing high RSSI
You're right, I didn't notice that the SBUS pin can be used as an analog input too.
May 24, 2017, 10:28 PM
Registered User
Thread OP
Quote:
Originally Posted by 007trains
Unfortunately USBASP won't appear as a standard com port, when i use USBASP in my arduino projects it seems to do a search for a USBASP device so it probably needs some software adaptation in order to use it with ULRS CC
Some users have used USBASP to flash ULRS, but that was independently from ULRS CC. I didn't plan to make it available from ULRS CC but that's a good idea and I've added it to the future features list.
May 24, 2017, 10:47 PM
FPV Melbourne
yak-54's Avatar
Nothing to see here move along
Last edited by yak-54; Feb 22, 2018 at 03:50 AM.
May 25, 2017, 01:30 AM
Registered User
Quote:
Originally Posted by athertop
Flip - your first statement is not entirely accurate. The servo connector labelled SBUS, is not in fact SBUS input on the pixhawk, but was originally designed as an SBUS output. You can however configure a parameter to turn this SBUS port into the RSSI analog input. It is 3.3v based input though and so a divider is required to reduce the 5v based output from the ULRS Mini boards.

It is mentioned here: http://ardupilot.org/copter/docs/com...-overview.html search for "Virtual Pin 103: RSSI"

The parameters:
BRD_SBUS_OUT - must be set to 0 (to disable SBUS output)
RSSI_TYPE - must be set to 1 for "Analog pin"
RSSI_ANA_PIN - must be set to 103 for that SB (SBUS out) port
There are also:
RSSI_PIN_LOW and RSSI_PIN_HIGH for low/high voltage readings on that input. On Pixhawk, PIN_HIGH would normally be 3.3. - for APM, would normally be 5.0

With the next release of ULRS, as you say, we will be able to select a channel where the RSSI value will be represented in the PWM value presented there. To have Arducopter use this we would use the parameters as follows:

RSSI_TYPE - must be set to 2 (for RCChannelPwmValue)
RSSI_CHANNEL - set to the channel number containing the PWM value
RSSI_CHAN_LOW - set to the PWM value representing low RSSI
RSSI_CHAN_HIGH - set to the PWM value representing high RSSI
That the way i am, are you using the filter?
May 25, 2017, 01:56 AM
Registered User
Thread OP
For now it's still mandatory to use the analog filter. Or you can wait a few days.

As an aleternative it's also possible to connect an analog meter to the RSSI pin (on TX side).
May 25, 2017, 02:34 AM
RC fanatic
Quote:
Originally Posted by waka_marbella
That the way i am, are you using the filter?
Yes, I made up a filter with a voltage divider to reduce to 3.3v max. I'm not that convinced with the accuracy though so holding out for the rssi over rc channel feature in next release.
May 25, 2017, 02:53 AM
Registered User
Thread OP
It's already running on my computer, see RSSI on channel 13 (selectable) :



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