- TrainCtl
- SLI
- Ultra
- Key
- Clock
- XMAS
- FanCtrl
- IRTank
- IRBetter
- Thermo
- MaryaToy
- MaryaBas
- PCTherm
- Servo
- MIC-II
- Video
- PIC17Dev
- Fuzzy
- RTOS1
- RTOS2
"MaryaToy" Project
This project was developed for my daughter to stop her from playing with the Thermistor based Digital Thermometer. This circuit is similar to the thermometer project, but uses shift registers to drive fifteen segment LED displays and a 74S138 for the common cathodes instead of the discrete transistors used in the previous project.
Click Here to look at the application's source code.
The circuit used for the final versoin of this application is given in the pdf file that you can look at Here.
The bill of materials for this application is:
| Part | Description |
|---|---|
| U1 | 7805 +5 Volt Regulator |
| U2 | 74S138, 3 to 8 Demultiplexor |
| U3 - U4 | 74LS374, 8 Bit Register |
| U5 | PIC16F84-04/P |
| Y1 | 4 MHz Ceramic Resonator with Internal Capacitors |
| 15 Segment | 6x 15 Segment Alpha-Numeric Common Cathode LED Displays |
| R1, R18, R19 | 10K, 1/4 Watt Resistors |
| R2 - R9, R11 - R17 | 220 Ohm, 1/4 Watt Resistors |
| R10 | 100 Ohm, 1/4 Watt Resistor |
| POT1 | 10K, Single Turn Potentiometer |
| C1 - C2 | 10 uF, 35 Volt Electrolytic Capacitors |
| C3 - C7 | 0.1 uF, 16 Volt Tantalum Capacitors |
| J1 | 9 Volt Battery Clip |
| SW1 | SPST Power Switch |
| SW2, SW4 | Momentary On Pushbutton Switch |
| Miscellaneous | Breadboard Prototyping System, Wiring |