Laptop/USB Pic Programming

[adamthole]

I am in the market for a new windows laptop, however before I buy one i want to make sure I can do my PIC programming with one. None of the new ones have serial or parallel ports on it. I was wondering what trouble I would have with using the USB port and one of teh USB programmers? Does all of the current PIC programming software support that? Some? None? Anything else I should know?

Thanks

 

[Exo]

an USB to RS232 converter cable allow you to use any serial port programmer out there... (good ones, not JDM)

 

[Joel Rainville]

Have you considered building and **broken link removed**? You could build the serial version and if the laptop doesn't have a serial port, use the RS232->USB converter Exo suggested. Or build the newer USB version right away.

The serial version has the advantage of being useable on any crappy old PC that has a serial port (and can run a version of MPLAB) *and* newer machines thanks to the USB converter. The USB version of ICD2 is obviously a no go on old machines without a USB port.

 

[Exo]

Also, the USB version of that ICD2 clone is based on a FT232 - A USB to RS232 converter chip...

So if you have to get that chip anyway, better use it to make a USB to RS232 cable, wich can be used for other purposes as well.

.

 

[adamthole]

Thanks, sounds great. I'll look ino the adapter cable!

 

[upand_at_them]

Just so you know...Some of the new laptop do indeed have a serial port. Most of the Dell Latitude machines do.

Mike

 

[eemage21]

If you're serious about electronics - I would strongly suggest you look for a laptop with both serial and parallel ports. I spent a lot of time looking for one, but when I finally bought it - it was money well spent. It doesn't take much space in the lab, I can use all my emulators, jtag programmers, you name it, withouth having to worry, if there's some incompatibilities with the USB.

 

[Nigel Goodwin]

Incidently, Elektor have just done an article on USB to Serial converters!, I found it EXTREMELY informative.

The way USB works means that speed of such a converter is SEVERELY limited, their tests showed that 9600 baud is the highest reliable transfer rate you can achieve!.

Also, toggling the handshake lines (as the JDM does) is even slower, under Windows XP they could toggle DTR at 40,000Hz using a proper serial port, with a USB to Serial converter this dropped to only 167Hz.

USB works in 'packets', serial ports work in bytes, a USB packet is sent every millisecond, and has to wait for acknowedgement - this means that the absolute fastest time to send a single byte through the converter is 3mS.

You can download the test software used from http://www.elektor-electronics.co.uk, the file is 050071-11.ZIP