Download Problem

[jaka]

LKK > I have just checked acouple of USB to serial adaptors and one of them has pin 1 connected to 0v. This is why it probably worked before. Pin 1 is normally screen so obviosly the manufacturer of the adaptor has connected this to ground (0v).

A null modem lead I checked also has pin 1 and 5 connected.

JAKA

 

[hippy]

There we go! Next question - could this have zapped a picaxe? We will find out shortly. Coz if you had carrier detect as ground and CD as the zero point reference and DTR going to RD and my brain has just exploded...

Thankfully PC serial ports rarely explode and are largely immune from mis-wiring. Which is just as well because mistakes like this could not only destroy the PICAXE ( or any other micro ) but also ruin a far more expensive PC.

People do seem to be very blasé about connecting whatever they build up to PC's, hoping it will work and then being surprised when it doesn't or even causes damage.

 

[hippy]

LKK > I have just checked acouple of USB to serial adaptors and one of them has pin 1 connected to 0v. This is why it probably worked before. Pin 1 is normally screen so obviosly the manufacturer of the adaptor has connected this to ground (0v).

That seems very dubious and wrong. Pin 1 is not ground/0V it is DCD. Any serial device it conncets to will have its DCD output shorted to 0V which could damage it.

A null modem lead I checked also has pin 1 and 5 connected.

That is more common, but it does depend on which end you are measuring and whether DTE or DCE, whether the short is local to each end or from end to end.

 

[jaka]

Hippy, you are right. I was checking this out with a 9/25 pin adaptor and 25 pin breakout box. I assumed pin 1 was the same on both. Sticking wires in the 9 pin and "belling them out" proved this to be not so.

That does not explain why the two adaptors are different.

I seem to remember that this adaptor didn't work on PLCs but did with a BS2. I won't try it on a picaxe.

Its about 7 years old, XP doesn't recognise it and Iv'e lost the drivers. So I'll bin it.

Thanks for my daily lesson.

Regards

JAKA

 

[hippy]

Its about 7 years old, XP doesn't recognise it and Iv'e lost the drivers. So I'll bin it.

Surely you mean "hack it open, have a look to see how it works, and see if it is useful in anyway"

 

[jaka]

Wheelie bins collected monday mornings, so gone. Thanks anyway.

 

[Dippy]

This has wheelie bin an interesting thread.