Plugin Modules

Several plug-in modules are available for microhope.

Digital Output Board:
This board has 8 LEDS with series resistors. It can be plugged into any of the four ports, the ground pin should be matched with that of the socket. Mainly used for displaying the  results of assembly language programs and code debugging.

 


Digital Input Board:
This board has 8 switches  with series resistors, one end connected to ground. Can be used for feeding 8 bit input data to programs.


R-2R DAC Board:
An 8 bit Digital to Analog Converter (DAC) is made using an R-2R network as shown in the schematic below. This can be used for generating arbitrary shaped voltage waveforms under software control.


Alphanumeric LCD board:
For some applications, it is necessary to have a local display. The HD44780 controller, or compatible IC, based LCD displays are widely available. They come with a 16 pin connector and the transfer protocol is well documented For details refer to . The connections between microHOPE and the LCD display are shown in figure. Pins 4,5 and 7 of the LCD display are control lines, connected to PC1, PC2 and PC4. The ASCII codes are transferred in the 4bit mode, using pins 11 to 14 connected to PC4, PC5, PC6 and PC7. The LCD should be connected to port C socket, to use the C library functions to access the display.



Motor Control Board:
The motor control board consists of 2 H-bridges (IC L293D). Board can be powered from outside or from the MicroHOPE socket. An INT/EXT jumper is provided to select the power option. The voltage level at the for outputs of L293 is decided by the four LSBs of the port on which it is connected. The outputs (A,B,C & D) can be used for controlling 2 DC motors or one stepper motor.

   

USBASP Programmer board:
    This is an open sourced ISP (In-System Programming) programmer available from http://www.fischl.de/usbasp/ . This is provided as an accessory to MicroHOPE due to several reasons. If you want to develop programs that uses the UART of Atmega32, you need to upload code using ISP. It can be used for programming other AVR micro-controllers also. It can be used for burning the boot loader. The LED on the board indicates power. It goes off while uploading code, giving an additional indication.