AXE027 PICAXE USB download cable
When the PICAXE system was first developed over ten years ago the ‘9 way serial port’ was the conventional way of connecting the computer to external devices, such as digital cameras.
The now-familiar PICAXE ‘3.5mm jack plug/socket’ connection was selected as (1) it is robust and (2) many early digital cameras used exactly the same serial download cable, meaning the cables were a low-cost mass produced item!
USB has now taken over this role and most modern laptops now only have USB-style connectors.
Unfortunately, the USB protocol is far more complex than the serial RS232 protocol; in fact it is not possible to implement the USB protocol on low-cost, limited-memory devices like 8 and 14-pin PICAXE microcontrollers. There simply isn’t enough memory space to implement both the USB protocol and the PICAXE firmware!
Therefore an alternate approach is required and that is to use a separate ‘intelligent’ USB cable with an embedded USB-to-serial converter chip, such as those made by FTDI. This gives the best of both worlds – a USB connection to the computer and a serial connection to the PICAXE chip itself.
As you can see, the AXE027 download cable contains a complete miniature circuit moulded into the USB connector.
This allows the cable to work via USB on all Windows, Linux and Mac computers.
To support PICAXE users who wish to use Linux or Mac computers to develop their PICAXE BASIC programs the new cross-platform AXEpad software is now available (Windows users should still use the Programming Editor software).