TTLogik is a device designed for experiments with logic (TTL, CMOS) circuits. It is the successor of the once in former Czechoslovakia popular Logitronik, Adam Elév, Kyber or a cheaper and simpler version of the contenporary Digital Logic Trainer, Pinokit Logic Trainer or a cheap no-name Logic Circuit Trainer Kit. Main purpose of the board is an educational use, see e.g. some student tasks (at the moment, in Slovak only, but with images).
Images of the produced board and example circuit.
The device consists of three parts: input, output and experimental. The middle, experimental part consists of a non-contact interconnect array with 300 contacts, on which almost any wiring can be created. The lower part contains four switches S1 to S4 of logic levels H and L (log. 1 = +5 V and log. 0 = 0 V). In addition, it contains one P button, which generates a shaped pulse without oscillations, suitable for sequential circuits. All signals are output to connector J1, from where they can be brought to any location on the experimental surface. Up to 3 common LSI circuits, e.g. 74xx series, can fit comfortably on the board.
The output section contains 5 red LEDs to indicate the logic level applied to inputs Q1, Q2, Q4, Q8 and Q16. The numbering has no other meaning than that it wants to indicate a binary sequence of inputs. In addition, the first four inputs Q1-8 are also fed to the input of the decoder, which converts the binary value to a number that is displayed on the two-digit seven-segment display. By changing the firmware, it is possible to change the 0-F hexadecimal display to a 0-15 decade display. After the display is switched off, it is switched on (and off again) by holding down the P button for a longer time. The inputs whose values we want to display are brought out on connector J2. This part of the device also contains the power supply. The possible ways of power supply are either via the X1 mains adapter with DC output voltage or via the micro USB connector from a powerbank, charger or computer. The USB input X2 is protected by a 250 mA fuse. Input and output processing, pulse P display and filtering is handled by the ATtiny2313A microprocessor, which can be reprogrammed via the ISP interface X3.
The complete wiring diagram is shown in the figure below.
![[schematic diagram]](/baloghr/TTLogic/blob/master/docs/images/TTLogik_schematic.png)
Schematic diagram. For the full-size image see /doc.
Technical parameters:
- Power supply via 5/2.1mm connector with positive center Uin 6-32V
- Power supply USB micro 5V with 250 mA fuse
- Number of outputs: 4 logic and 1 pulse
- Number of inputs: 5 logic, including 4 for display
- uP - Atmel ATtiny2313A
- /Firmware - source code for microcontroller and Arduino sketches for testing
- /Hardware - All KiCAD design files (schematic, PCB, gerber files)
See this interactive diagram for helpwith the orientation on the board, you can also use it to check the obtained/populatd components when building your own copy of the board.
The design rules are set up for JLCPCB, but double-check they fit your needs before using them.
- v1.0 Initial release
The hardware is released under CERN Open Hardware Licence Version 2 - Permissive (CERN OHL v2 Permissive). All other code is open source so please feel free to do anything you want with it.
THE HARDWARE AND SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
This repo was created using an Open Hardware Template