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Quad Rover/ Propeller help requested

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  • Hi

    I presume we are assuming that the positive 5v sent to the servo's from the receiver is commoned with the 5v on the connector labelled bat on the receiver, because the power to the receiver is actually supplied from the prop board to the receiver via the servo connectors in this scenario. Is that a good assumption?

    Clutching at straws- it must be something simple as I don't see how code in existence for so long can be wrong.

    Dave

  • PublisonPublison Posts: 12,164

    What do you have on VIN for battery power?

  • PublisonPublison Posts: 12,164

    Remind me ..how is the receiver powered (pins above Channel1) .

  • @Publison said:
    You posted this in the Activity page:
    "Finally, when we start the gas powered motor and it's running, two of the wheels on one side of the rover rotate but the wheels on the other side don't rotate. Any idea why this is?"

    Does this still happen?

    No. That was happening before we uploaded programs to the Propeller board. Now all four wheels spin forward when the gas powered motor is started up.

  • @Publison said:
    I'm wondering if the 10k series resistors on the AUX I/O input are a little high for your receiver.

    @Publison said:
    I'm wondering if the 10k series resistors on the AUX I/O input are a little high for your receiver.

    Interesting thought. How would we “disable” (?) the resistors on the Propeller board? Is that even possible?

  • @Publison said:
    Today's thoughts...You said you connected the receiver to stand-alone servos, where they the servos on the QR? What happens when you connect the servos on the QR directly to the receiver with power and the power switch in the SERVO and POWER position .
    Sounds like the transmitter and receiver are working correctly as you found out at the hobby shop.

    Software has been stable for >10 years so I really don't think that's the problem, but I could be wrong. I'm thinking it MIGHT be a hardware problem. I hope not. The prototype QR was built on a Project Board and can be duplicated if I can get the original parts list from David Carrier at Parallax. The QR Control Board is no longer available.

    Has your QuadRover ever run before when you first got it?

    No, the QuadRover was never run before to my knowledge. This is the first time it’s run.
    What are your thoughts on completely replacing the Propeller board?

  • PublisonPublison Posts: 12,164

    That's a new scenario that was not communicated before.

  • PublisonPublison Posts: 12,164

    @tritonium said:
    Hi

    I presume we are assuming that the positive 5v sent to the servo's from the receiver is commoned with the 5v on the connector labelled bat on the receiver, because the power to the receiver is actually supplied from the prop board to the receiver via the servo connectors in this scenario. Is that a good assumption?

    Clutching at straws- it must be something simple as I don't see how code in existence for so long can be wrong.

    Dave

    The receiver should be powered when power switch is the most upward position. I supplies power to all servos and I'm assuming to the receiver also base on old servos that I have owned.

  • @Publison said:
    That's a new scenario that was not communicated before.

    @Publison said:
    That's a new scenario that was not communicated before.

    How might that factor in?

  • PublisonPublison Posts: 12,164
    edited 2021-10-07 22:45

    @"Mark Kibler" said:

    @Publison said:
    Today's thoughts...You said you connected the receiver to stand-alone servos, where they the servos on the QR? What happens when you connect the servos on the QR directly to the receiver with power and the power switch in the SERVO and POWER position .
    Sounds like the transmitter and receiver are working correctly as you found out at the hobby shop.

    Software has been stable for >10 years so I really don't think that's the problem, but I could be wrong. I'm thinking it MIGHT be a hardware problem. I hope not. The prototype QR was built on a Project Board and can be duplicated if I can get the original parts list from David Carrier at Parallax. The QR Control Board is no longer available.

    Has your QuadRover ever run before when you first got it?

    No, the QuadRover was never run before to my knowledge. This is the first time it’s run.
    What are your thoughts on completely replacing the Propeller board?

    Someone buy me a plane ticket to Connecticut to get a replacement board in storage. :)

    I have a couple of Parallax Project boards that I can try to put something together. I have all the prototype software that went with it. Just have to find the FETs that they used.

  • PublisonPublison Posts: 12,164

    I know Ken has/had a Quadrover back in the Rocklin Museum . Maybe you can borrow that controller board?

  • @Publison said:
    I know Ken has/had a Quadrover back in the Rocklin Museum . Maybe you can borrow that controller board?

    It's just a Propeller 1 board, isn't it? There must be a few kicking around on-line?

  • PublisonPublison Posts: 12,164

    That particular board has been long gone for 10 years. Only 15-20 were made. It can be easily replicated with Propeller boards available now. Researching now for parts.
    I think I have an extra in Connecticut but I will not be up there for two months.

  • PublisonPublison Posts: 12,164

    @"Mark Kibler" said:

    @Publison said:
    I know Ken has/had a Quadrover back in the Rocklin Museum . Maybe you can borrow that controller board?

    It's just a Propeller 1 board, isn't it? There must be a few kicking around on-line?

    Yes it's just a Prop1.

  • @Publison said:
    Remind me ..how is the receiver powered (pins above Channel1) .

    Not sure how to check this. The RC receiver is powered/ gets voltage through the Propeller board.

  • @Publison said:
    That particular board has been long gone for 10 years. Only 15-20 were made. It can be easily replicated with Propeller boards available now. Researching now for parts.
    I think I have an extra in Connecticut but I will not be up there for two months.

    Road trip? ;-)

  • Mark KiblerMark Kibler Posts: 545
    edited 2021-10-08 00:17

    @tritonium said:
    Hi

    I presume we are assuming that the positive 5v sent to the servo's from the receiver is commoned with the 5v on the connector labelled bat on the receiver, because the power to the receiver is actually supplied from the prop board to the receiver via the servo connectors in this scenario. Is that a good assumption?

    Clutching at straws- it must be something simple as I don't see how code in existence for so long can be wrong.

    Dave

    Dave,

    There is NO 3 pin, black-red-white wire going to the receiver's BAT input port. That slot is empty. There are 4 wires for 4 channels and they connect to the Propeller board at 8, 9, 10, and 11 respectively (see photo). When the Propeller board is powered on, you push the 'on' button on the receiver and it powers up. Then you 'bind' (synchronize) the signal from the RC transmitter and receiver by pressing a button on the transmitter.

    It's noteworthy that Quad Rover's throttle servo pulse when the program "QuadRoverControl_v1.0 " is run. This tells me that the throttle servo is getting some sort of signal from somewhere. From the Propeller board/ program...? See previous post #17:

    "Running QuadRoverControl_v1.0 by itself **causes the throttle servo to pulse ** until the Propeller board is shut off. The servo does not respond to a signal from the remote control transmitter/ receiver.

  • Hi

    Yes that was my point- the receiver BAT is not connected, so for this to work it must be supposed to receive its power through the servo connectors from the prop board. That assumes there is a common connection between all the +5v pins on the receiver- and this sounds reasonable- but it doesn't work- so perhaps there might be a good reason for the manufacturer to not common all the 5v connections. It would be interesting to measure what voltage appears on the +5 BAT pin. That's all I was proposing.

    Dave

  • @tritonium said:
    Hi

    Yes that was my point- the receiver BAT is not connected, so for this to work it must be supposed to receive its power through the servo connectors from the prop board. That assumes there is a common connection between all the +5v pins on the receiver- and this sounds reasonable- but it doesn't work- so perhaps there might be a good reason for the manufacturer to not common all the 5v connections. It would be interesting to measure what voltage appears on the +5 BAT pin. That's all I was proposing.

    Dave

    The receiver powers up when the Propeller board is powered up. the receiver seems to be drawing voltage through the Propeller board. How else could it power on when the Propeller board is turned on? With that said --- What are your thoughts on connecting a battery to the receiver along with the four wires that are already there?

  • @"Mark Kibler" said:

    @tritonium said:
    Hi

    Yes that was my point- the receiver BAT is not connected, so for this to work it must be supposed to receive its power through the servo connectors from the prop board. That assumes there is a common connection between all the +5v pins on the receiver- and this sounds reasonable- but it doesn't work- so perhaps there might be a good reason for the manufacturer to not common all the 5v connections. It would be interesting to measure what voltage appears on the +5 BAT pin. That's all I was proposing.

    Dave

    The receiver powers up when the Propeller board is powered up. the receiver seems to be drawing voltage through the Propeller board. How else could it power on when the Propeller board is turned on? With that said --- What are your thoughts on connecting a battery to the receiver along with the four wires that are already there?

    Adding a fifth wire and then powering the RC receiver independent of power from the Propeller board did nothing...

    It may be noteworthy that when I plugged the battery into the RC receiver, the Propeller board's blue light also came on.

  • PublisonPublison Posts: 12,164

    I'm out at doctors for the day.

  • Hi

    It may be noteworthy that when I plugged the battery into the RC receiver, the Propeller board's blue light also came on.

    Do you mean that when you plugged the battery into the RC receiver you had no other power going to the propeller?
    Is that the same battery you were using for the propeller?

    The words "No signal" appear horizontally and vertically on the text screen (see attached screen shot) but the words 'Right X: Not set", etc. do NOT appear below "No signal"

    That's got to be a clue- but what to make of it? Individually everything works- but not when connected together!
    Connections, power levels, clock rate, noise, damage..... I'm sure 5 minutes with a scope will show what's happening- can you lay your hands on one?

    Dave

  • Mark KiblerMark Kibler Posts: 545
    edited 2021-10-08 22:03

    Do you mean that when you plugged the battery into the RC receiver you had no other power going to the propeller?

    No. Before we plugged the battery into the RC receiver there was power to the receiver that had to be coming through the Propeller board. Next we connected a stand-alone battery to the RC receiver. When we did, the Propeller board’s blue light also came on. Finally we powered the Propeller board on AND ran stand-alone power to the RC receiver. Then we ran the SetTrim program to test the servos. Same result: a “No signal” message on the Propeller board text screen.

    Is that the same battery you were using for the propeller?

    No. Two separate batteries

    Dave

    I don’t have access to a scope but I do have a multimeter.

  • Hi

    Running out of ideas.
    Can you measure the voltage of the battery you are connecting to the prop board, when it is connected and switched on?
    If someone else doesn't step in I will see if I can write some simple test code.

    Dave

  • Mark KiblerMark Kibler Posts: 545
    edited 2021-10-09 16:46

    @tritonium said:

    Can you measure the voltage of the battery you are connecting to the prop board, when it is connected and switched on?

    Voltage measured at the battery terminals is 9.2 volts. It’s a standard 9 volt rectangular battery. When it’s connected to the RC receiver, then to the Propeller board; and when voltage is measured at the input pin #8 (red wire), voltage is ZERO. When voltage is measured at the BLACK wire —-> #8 GND pin, voltage is positive 4.0 volts.
    Voltage input from the Propeller board, through the receiver, then to the middle pin (red receiver wire) at the three-pin Propeller input slot #8 is 5.0 volts. The stand-alone battery was not attached. The voltage comes from the Propeller board (white wires?? ) I understood from the documentation that the white wire carries the signal (program?) from the computer to the Propeller board.
    Maybe I should power up the Propeller board, then connect the 9.0 volt battery, then measure voltage from the receiver’s red wire at the #8 middle pin and see what the voltage is. That would tell us where the power comes from to the receiver when the Propeller board is turned on.
    The problem seems to be with the signal and parts of the program not coming through the RC receiver to the Propeller board, not with the voltage.

    What are everyone’s thought at this point?

  • @tritonium said:
    Hi
    If someone else doesn't step in I will see if I can write some simple test code.

    Dave

    Thanks for the offer; that’s a good plan. I wonder which parts of the program are getting through the RC receiver to the Propeller board, then to the servos…?

  • Hi

    I don't understand what you are saying.

    It’s a standard 9 volt rectangular battery. When it’s connected to the RC receiver, then to the Propeller board...

    What does that mean. I thought you had two power sources (batterys) one for the receiver, the other for the prop.
    Doesn't the receiver run off 5v?

    and when voltage is measured at the input pin #8 (red wire), voltage is ZERO

    How can that be??- Is the meter connected with the negative meter lead connected to prop gnd (0v)? If so the red servo wire should read +5v as it is the 5v pin, but you call it input (which input, power or signal) the black is gnd (0v) and the white is signal.
    With the transmitter switched on and the servo connected to its power and the prop to its power then (with the meter negative lead connected to prop gnd(0v)) I would expect to see +5v on the red servo wire, 0v on the black wire and almost nothing maybe a little voltage on the white signal wire, which may vary a little (tiny bit) when the relevant transmitter stick is moved.

    Dave

  • PublisonPublison Posts: 12,164

    Voltage at the receiver(+5) should only be available on the center of the three pin connector when the power switch is in Power/Servo ON position. Some receivers do not need the Battery connection usually being fed from a BEC, but rather the whole receiver can be powered from the center pin.

  • PublisonPublison Posts: 12,164

    What is the voltage on the 12 volt battery that came with the unit. What voltage does it read when connected to VIN and the power switch is is POWER/SERVO position?

  • PublisonPublison Posts: 12,164
    edited 2021-10-09 19:28

    @"Mark Kibler" said:

    @tritonium said:

    Can you measure the voltage of the battery you are connecting to the prop board, when it is connected and switched on?

    Voltage measured at the battery terminals is 9.2 volts. It’s a standard 9 volt rectangular battery. When it’s connected to the RC receiver, then to the Propeller board; and when voltage is measured at the input pin #8 (red wire), voltage is ZERO. When voltage is measured at the BLACK wire —-> #8 GND pin, voltage is positive 4.0 volts.
    Voltage input from the Propeller board, through the receiver, then to the middle pin (red receiver wire) at the three-pin Propeller input slot #8 is 5.0 volts. The stand-alone battery was not attached. The voltage comes from the Propeller board (white wires?? ) I understood from the documentation that the white wire carries the signal (program?) from the computer to the Propeller board.
    Maybe I should power up the Propeller board, then connect the 9.0 volt battery, then measure voltage from the receiver’s red wire at the #8 middle pin and see what the voltage is. That would tell us where the power comes from to the receiver when the Propeller board is turned on.
    The problem seems to be with the signal and parts of the program not coming through the RC receiver to the Propeller board, not with the voltage.

    What are everyone’s thought at this point?

    A 9 Volt Battery is not going to cut it. There is very little current in that battery. Get rid of that and connect the original 12 volt battery. Charge it if needed or buy a replacement so you are starting at new.

    If voltage at the BLACK wire measures 4.0 volts then something is connected backwards.

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