# Proteus Help

#### elektroshok

Joined May 24, 2023
13
I want to write my name and surname with LEDs in proteus. Only logic gates(flip-flop is not allowed) and 555 timer are allowed. I made a model prior to this, which is basically a binary to decimal converting LED. But I am stuck on this one. Any recommendation?

#### Papabravo

Joined Feb 24, 2006
20,383
Are you thinking of dot matrix letters or 7-segment letters, or something else from a professor's fevered brain? On a practical note, a microcontroller is the ONLY viable approach. Any other approach is like running around in circles of ever-increasing radius.

#### elektroshok

Joined May 24, 2023
13
Are you thinking of dot matrix letters or 7-segment letters, or something else from a professor's fevered brain? On a practical note, a microcontroller is the ONLY viable approach. Any other approach is like running around in circles of ever-increasing radius.
7 segment letters. Totally agree with you, but the course is about logic design and we are expected to make our design using only logic gates. I nearly understood the logic behind BTD 7 segment display but having a hard time implementing this into alphabet.

#### Papabravo

Joined Feb 24, 2006
20,383
7 segment letters. Totally agree with you, but the course is about logic design and we are expected to make our design using only logic gates. I nearly understood the logic behind BTD 7 segment display but having a hard time implementing this into alphabet.
I remember seeing a suggested design for doing letters on a 7-segment display. It was an odd mix of upper and lower case and looked "really funky" -- at least to me. Let me see what I can find.

Here you go, it is a start. Note, some letters are admittedly unrecognizable by most people.
https://en.wikichip.org/wiki/seven-segment_display/representing_letters

#### elektroshok

Joined May 24, 2023
13
I remember seeing a suggested design for doing letters on a 7-segment display. It was an odd mix of upper and lower case and looked "really funky" -- at least to me. Let me see what I can find.
I'd really appreciate it

#### elektroshok

Joined May 24, 2023
13
I remember seeing a suggested design for doing letters on a 7-segment display. It was an odd mix of upper and lower case and looked "really funky" -- at least to me. Let me see what I can find.

Here you go, it is a start. Note, some letters are admittedly unrecognizable by most people.
https://en.wikichip.org/wiki/seven-segment_display/representing_letters
I managed to match the binary values to characters of my name. But how can i make it automatic with 555 timer, where should i connect it? Do you have any idea?

#### Papabravo

Joined Feb 24, 2006
20,383
I really don't since I cannot read your mind on what you want it to look like. Do you want the characters to just show up on the displays, or do you want them to scroll from right to left across your line of sight.

#### elektroshok

Joined May 24, 2023
13
I really don't since I cannot read your mind on what you want it to look like. Do you want the characters to just show up on the displays, or do you want them to scroll from right to left across your line of sight.
It must show up one by one with 1 second interval. For example for your name P for 1 sec, A for 1 sec ,P for 1 sec, A for 1 sec. I will use just one led

#### Papabravo

Joined Feb 24, 2006
20,383
So it looks like you could use a shift register and a display register. You would have an initialization phase that would load the shift register with 8 bits for every letter in your name. The serial output of this register would be looped back to the serial input. You would use 8 clock pulses to move the shift register by one character. Then you would load those 8 bits into the display register.

Do you understand what I have described?

#### elektroshok

Joined May 24, 2023
13
So it looks like you could use a shift register and a display register. You would have an initialization phase that would load the shift register with 8 bits for every letter in your name. The serial output of this register would be looped back to the serial input. You would use 8 clock pulses to move the shift register by one character. Then you would load those 8 bits into the display register.

Do you understand what I have described?
So so. Is there an example you can provide? Thanks for your help by the way

#### Papabravo

Joined Feb 24, 2006
20,383
So so. Is there an example you can provide? Thanks for your help by the way
The only similar thing I did was a communications packet blaster. It used a FIFO memory (IDT7201) to repeatedly send the same packet to a communications system at a periodic rate. It was for testing the physical layer and cable system. It was controlled by a state machine (Moore) and implemented in a large (for the time) PAL (82S105). Using a language called ABEL. That was more than 40 years ago, and I was not able to keep the schematics or the PAL equations.

https://www.renesas.com/us/en/document/dst/720072017202-datasheet?r=13455
https://www.datasheets.com/en/part-details/82s105-bxa-teledyne-e2v-42132609

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