martinwinlow
New Member
Hi,
I hope someone can help with this...
I have an old PICAXE-based project that I resurrected to try to test the serial port on an old laptop that I want to use for some legacy work (connecting to the digital inverter on a 2007 electric Ford Transit conversion).
First I confirmed the PICAXE project was still working and sending text data out using the project's original 3.5mm stereo jack connector and using the AXE027 serial-USB lead to connect project to laptop and it worked normally, outputting the text that the project generates into Hyperterminal running on the laptop.
Then I tried using a CH340 RS232-USB adaptor and despite connecting the Tx wire and ground connections from the PICAXE stereo jack to the correct pins on the CH340's USB port got no output. So I tinkered... and to my surprise found that with PICAXE gnd connected to (CH340 DB9)Pin 5 and PICAXE TD connected to (CH340 DB9)Pin 4 ('DTR' pin, not 'RD' Pin 2 as I understand it should be) the serial output appears correctly in the Hyperterminal window! What the heck is going on?!
I would also welcome a suggestion as to how I can test the laptop's serial port. I want to be sure it works properly before I try connecting to the Transit's inverter.
Thanks in advance, Martin Winlow.
I hope someone can help with this...
I have an old PICAXE-based project that I resurrected to try to test the serial port on an old laptop that I want to use for some legacy work (connecting to the digital inverter on a 2007 electric Ford Transit conversion).
First I confirmed the PICAXE project was still working and sending text data out using the project's original 3.5mm stereo jack connector and using the AXE027 serial-USB lead to connect project to laptop and it worked normally, outputting the text that the project generates into Hyperterminal running on the laptop.
Then I tried using a CH340 RS232-USB adaptor and despite connecting the Tx wire and ground connections from the PICAXE stereo jack to the correct pins on the CH340's USB port got no output. So I tinkered... and to my surprise found that with PICAXE gnd connected to (CH340 DB9)Pin 5 and PICAXE TD connected to (CH340 DB9)Pin 4 ('DTR' pin, not 'RD' Pin 2 as I understand it should be) the serial output appears correctly in the Hyperterminal window! What the heck is going on?!
I would also welcome a suggestion as to how I can test the laptop's serial port. I want to be sure it works properly before I try connecting to the Transit's inverter.
Thanks in advance, Martin Winlow.