Can I use a Generic USB to 3.5mm jack instead of a AXE027?
- Thread starter Gaetano
- Start date
What's a "Generic USB to 3.5mm jack"? The AXE027 contains a USB-to-serial converter and a USB sound card won't work if hat's what you mean.
However you can use a normal cheap USB-to-serial converter with the cheap PICAXE serial programming cable or with a DIY programming cable.
However you can use a normal cheap USB-to-serial converter with the cheap PICAXE serial programming cable or with a DIY programming cable.
Yes, thats exactly what I meant, I found on ebay a USB to 3.5mm jack cable. I have previously used USB - serial converters when we were using serial cables on old pcs. I read on the official picaxe web site that they prefer the use of the USB cable because it says the following "This USB cable is a 5V logic level device, so works far better than a 'serial cable + universal USB-RS232 adapter' combination when, for instance, calibrating touch sensors with the PICAXE software". I want the cable for general programming of vehicles and will not use add on sensors for projects. So would you consider the serial with a USB converter a viable option? Thank you
Yes I would.
The only advantage of using the more expensive logic level cable is that you don't need to use the enhanced download circuit to prevent it from interfering with analogue and touch sensors when connected. If you don't want to use the enhanced download circuit, then disconnecting the Serial In line from the PICAXE will prevent the RS232 cable from affecting touch and ADC readings when it is connected.
I assume you guys are referring to using a 'prolific' USB to serial device. There are lots available on eBay for just a few buck each. I am planning to try one soon since my latest notebook no longer has a serial port. I am also keen to try the android terminal referred to on the forum.
- Daryl
- Daryl
Just make sure that you don't buy a counterfeit one!
Also you need to be aware that not all USB-to-serial cables that don't work with PICAXE are counterfeit - but all genuine Prolific ones will work with PICAXE. The drivers can be found here.
What causes the incompatibility is that these adaptors do not support break signalling (outputting a constant mark - a high signal for RS232) and break signalling is used to tell the PICAXE that the computer wants to download a program on to it and then the PICAXE will respond then the computer will start sending serial data to the PICAXE. Break signalling eliminates the need for an RTS or DTR line which would require a costly four pole 3.5mm jack.
If the adaptor doesn't support break signalling then not only would you not be able to program the PICAXE, but the LED test in Programming Editor would fail even though the loopback test will pass.
What causes the incompatibility is that these adaptors do not support break signalling (outputting a constant mark - a high signal for RS232) and break signalling is used to tell the PICAXE that the computer wants to download a program on to it and then the PICAXE will respond then the computer will start sending serial data to the PICAXE. Break signalling eliminates the need for an RTS or DTR line which would require a costly four pole 3.5mm jack.
If the adaptor doesn't support break signalling then not only would you not be able to program the PICAXE, but the LED test in Programming Editor would fail even though the loopback test will pass.
erco
Senior Member
Check out goeytex's post about adding an inverter to cheap USB adapters. The mod worked great for me.
http://www.picaxeforum.co.uk/showthread.php?18715-problem-with-downloading-the-program-onto-the-picaxe&p=174475&viewfull=1#post174475
http://www.picaxeforum.co.uk/showthread.php?18715-problem-with-downloading-the-program-onto-the-picaxe&p=174475&viewfull=1#post174475
lbenson
Senior Member
Regarding the CP2102 usb adaptors which put out an inverted signal (respective to picaxe programming needs), I would guess that the polarity of the i/o is programmable. Does anyone have a link to CP2102 driver information which might say how we could program the chip or alter the driver to make it suitable?
I use these inexpensive adaptors to talk to the picaxe with serin/serout, but use the db9 usb/serial dongles with a made-up cable for pins 2, 3, and 9 to do the programming.
I use these inexpensive adaptors to talk to the picaxe with serin/serout, but use the db9 usb/serial dongles with a made-up cable for pins 2, 3, and 9 to do the programming.