[Diego Spinola] wrote in to tell us about a node communication system he’s been working on called HsNet. The aim is to build a system of nodes that can be made up of small and inexpensive microcontrollers. The problem is that the least expensive controllers often don’t have a hardware UART. HsNet implements the RS485 protocol using a software UART along with a slim and sleek addressing scheme.
The first module developed, seen in the image above and video after the break, is a single channel pulse-width-modulation node using a PIC 12F683. It can be sent commands in the payload of the HsNet packet format. The PWM modules accept three different commands; one is a desired PWM value, another is a delay between steps for the PWM, and the last toggles a blink function.
He has also developed an analog sensor module and an Arduino-based TCP/IC gateway module. Now that the packet communications have been established, it will be rather simple to add nodes based on that groundwork. [Diego] brought these components together to build an interactive wall which can also be seen after the break.