Thinklabs UNIBOARD V1.1, User Manual, Page: 114 / 129

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What you can do with the uNiBoard
This section describes the purpose of every sample Code given in the CD’s uNiBoard Contents directory
which contains the sample codes for RTOS based and Non-RTOS.
NOTE: The sample code given contains the Makefile. You need to rename the Makefile_LINUX to Makefile
for Linux OS and similarly Makefile_WINDOWS to Makefile for Windows OS while using the code.
In Non-RTOS based sample codes we will describe in short what the code is meant for and what sort of
output it will demonstrate:
1. PORTS
The LEDS are connected to one of the general purpose port (PORTC) available of the ATmega128. These
LEDs are connected using the FRC cable. The open FRC connectors are given on the uNiBoard so that
their status can be monitored by interfacing them to LEDs using the FRC cable.
2. Timer0 using Interrupt
The Software clock is implemented using hardware timer, Timer0 in Normal mode such that it generated
and Interrupt after every 1ms. The Board’s Crystal is 16MHZ and PRESCALAR is set to 1024 therefore
16MHZ/1024 = 0.000064 sec (resolution of timer). So for timer to overflow for every 1ms we need to
load the count ((256 – 15) =241) as 0.000064 * 15 = 0.96 msec ~ 1msec. The clock is displayed on LCD
and UART.
3. Switches
The Switches on the uNiBoard are connected to general purpose port pins of the controller. So you can
use this switches for reading the inputs from the user. The SW1 is connected to PORTDS’s PIN7 and SW2
is connected to PORTD’s PIN6 of the controller.
4. EEPROM
The ATmega128 has an on-chip EEPROM (4KB) so that you can use it to store the non-volatile data. The
code contains the some library functions so that you can store the contents in a particular pattern or
same data at locations by specifying start address and end address. The output is debugged on serial
window. EESAVE fuse bit has to be enabled or else on every programming cycle the EEPROM will also be
erased along with flash.
5. Joystick and VT library
The Joystick (analog joystick of PS2 fame) is used as a mouse on the serial window in this sample
example. The Joystick X axis is connected to the on-chip ADC channel 1 and Y axis to channel 2. The ADC
is configured such that it gives an interrupt after the conversion is over. Since only one ADC channel
conversion is done at a time so we need to reconfigure it for other channel. The ADC conversion value is
stored in ADC’s Data register.