LEDs Boards

Four LED boards were constructed, each consisting of 10 Light Emitting Diodes in four different colours.(1 Blue, 3 green, 3 yellow, 3 red). The LEDs represent the sensor readings from low to high starting from blue.

The LED boards are connected to Robostix via its second serial port (UART1). A custom protocol was designed for the LED boards. The protocol defines the commands necessary to switch on/off the LEDs and how to address each LED board. The protocol is thoroughly described in later sections of this document.

Figure 3.11 shows the four LED boards.

Figure 3.11: LED boards.

This LED board uses the CRD89C51RD microprocessor offered by Cyrod Technologies [32]. It features a standard 8051 core alongside a 64K flash memory for storing the application code and 1k of RAM for application data. The program can be updated on the target board through the embedded ISP function of the processor. Up to 36 input/output pins are available alongside a rich set of peripherals like counters/timers, watchdog timer, PWM facility etc.