Ultrasonic SRF05 connect to PIXAXE 20M2 AXE 118 board
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Hi,
Yes probably, but the exact circuit/software may depend if it is a "genuine" SRF 05 (from the PICaxe Store / Rev. Ed.) or a "Chinese Copy", for example from Ebay.
There should be a number of threads on this forum (concerning both types) for example HERE, but I believe the "preferred" method is to use a single pin (which must be Input/Output compatible), probably without a pull-down resistor present, for the Transmit and Receive (echo) signals.
Cheers, Alan.
Yes probably, but the exact circuit/software may depend if it is a "genuine" SRF 05 (from the PICaxe Store / Rev. Ed.) or a "Chinese Copy", for example from Ebay.
There should be a number of threads on this forum (concerning both types) for example HERE, but I believe the "preferred" method is to use a single pin (which must be Input/Output compatible), probably without a pull-down resistor present, for the Transmit and Receive (echo) signals.
Cheers, Alan.
Ultrasonic SRF05 connect to PIXAXE 20M2 AXE 118 board
Thank you but I am only trying to sort out the board I bought from PICAXE stores - I assume that there must be a way to connect the Ultrasonic SRF05 to the PIXAXE 20M2 AXE 118 board. I assumed if I bought from PICAXE I would be able to use.
Are there any help guides available
Thanks
Thank you but I am only trying to sort out the board I bought from PICAXE stores - I assume that there must be a way to connect the Ultrasonic SRF05 to the PIXAXE 20M2 AXE 118 board. I assumed if I bought from PICAXE I would be able to use.
Are there any help guides available
Thanks
Aries
New Member
Presumably you have already looked at this ...
inglewoodpete
Senior Member
Certainly possible. While I have used both the SRF05 board and several AXE118 boards, I have not used them together. I no longer have the hardware due to the work being done under contract for a client 15 years ago. So I'm a bit rusty on interfacing the SRF05.
When I opened the datasheet for the AXE118, I noticed that document described the use of an earlier PICAXE, the 20M. The 20M2 is a much more flexible and capable chip, with almost all I/O pins being configurable as inputs or outputs. The PICAXE pins on the left all have a resistor array arranged as pull-downs. This may interfere with the operation of the SRF05, so I suggest you don't use those pins on the PICAXE.
My suggestion would be to use one or two of the pins on the right of the PICAXE: B.0 to B.7. However, to access both the input and output capabilities of these pin you will need to wire the SRF05's I/O into the wiring points between the PICAXE and the ULN2803 chip (IC2). You would not use the ULN2803 (or equivalent) chip because it can only be used as an output buffer/driver and not as an input to the PICAXE.
When I opened the datasheet for the AXE118, I noticed that document described the use of an earlier PICAXE, the 20M. The 20M2 is a much more flexible and capable chip, with almost all I/O pins being configurable as inputs or outputs. The PICAXE pins on the left all have a resistor array arranged as pull-downs. This may interfere with the operation of the SRF05, so I suggest you don't use those pins on the PICAXE.
My suggestion would be to use one or two of the pins on the right of the PICAXE: B.0 to B.7. However, to access both the input and output capabilities of these pin you will need to wire the SRF05's I/O into the wiring points between the PICAXE and the ULN2803 chip (IC2). You would not use the ULN2803 (or equivalent) chip because it can only be used as an output buffer/driver and not as an input to the PICAXE.
Simplest way is 3 pin mode (using 3 way header on SRF005 + wire link on 5 pin header as per the SRF005 datasheet)
You can use direct connection to any any i/o pin as others have said, but C.0 is convenient.
SIG to pin C.0 (leave off resistors RPU and RPD, so SRF005 is the only connection on that pin)
5V to V+
0V to 0V
You can use direct connection to any any i/o pin as others have said, but C.0 is convenient.
SIG to pin C.0 (leave off resistors RPU and RPD, so SRF005 is the only connection on that pin)
5V to V+
0V to 0V
Please see page 1 i.e. "using the 3 way header" of the datasheet https://picaxe.com/docs/srf005.pdf
If you don't have a 3 pin header at the top of the sensor and/or have pins physically marked Echo and Trigger (instead of SIG) then it is NOT a SRF005 from the PICAXE store as previously implied, it is a chinese copy device sourced elsewhere, and will need connecting as per links in AllyCat post 2 above i.e. TRIG pin to C.0 and also ECHO pin to C.0 through a 1.8k resistor
If you don't have a 3 pin header at the top of the sensor and/or have pins physically marked Echo and Trigger (instead of SIG) then it is NOT a SRF005 from the PICAXE store as previously implied, it is a chinese copy device sourced elsewhere, and will need connecting as per links in AllyCat post 2 above i.e. TRIG pin to C.0 and also ECHO pin to C.0 through a 1.8k resistor
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Aries
New Member
I think this is fairly explicit (for ECHO read ECO)
Try using the code for using the HC-SR04 that is posted here
Do not add anything to RPU or RPO on your AXE118 board. These are nothing to do with the HC-SR04.
I do not own a HC-SR04 but a web search shows that it has 4 pins labeled Vcc, Trig, Echo & GND.
You connect the 1.8K resistor between the Trig and Echo pins on the HC-SR04 and the code in the link I gave you connects the trigger pin on the HC-SR04 to pin C2 on the PICAXE chip.