I recieved 74HC148 and I tried to verify it with ESP32, 7 switches, and 7 resisters(12K). The result was not what was expected. IMG_20181015_074512.jpg Here is my codes. void setup() { pinMode(12, INPUT); pinMode(13, INPUT); pinMode(14, INPUT); Serial.begin(115200); } void loop() { byte res1 = (GPIO...

I added diodes(one diode per one button) to my circuit, but I can't press multiple buttons at the same time.
hmm...

To Tom Meyers, Thank you for your advice. I do appreciate it. I ordered 74HC148 yesterday and I will receive it tomorrow. So, I'll try to verify that 74HC148 with ESP32 works correctly. Maybe, as is the case with 74HC138, 74HC148 used with ESP32 doesn't work correctly. To all, I used universal board...

Hello, ESP_Sprite. I appreciate you giving me the advice. Yosuke: I'm not quite sure why you get the results you do... the only thing that springs to mind immediately is that your breadboard setup has a fairly big parasitic capacitance, and the pull-up in GPIO16 may not be enough to overpower it. Yo...

Hi, Tom.

I will try 74HC148 as well.
Thanks for helping me and showing me the datasheet.
I really appreciate it.

Yosuke

Hello, Tom Meyers.
Thanks for taking the time to reply.
It took a long time to edit schematic. But I managed to do it.
Here is my schematic. My key matrix circuit doesn't work yet.
So, please tell me if you know something about this.

Yosuke

Hi, ESP_Sprite. Thank you for advicing me. Here is my code(Version 2). //Mux control pins int s0 = 12; int s1 = 13; int s2 = 14; int controlPin[] = {s0, s1, s2}; int muxChannel[8][3] = { {0, 0, 0}, //channel 0 {1, 0, 0}, //channel 1 {0, 1, 0}, //channel 2 {1, 1, 0}, //channel 3 {0, 0, 1}, //channel ...

I'm trying to build key matrix circuit by ESP32 and 74HC138, but it doesn't work. The circuit is below. IMG_20181006_171559.jpg IMG_20181006_171658.jpg When I push one of the switches, I want to get their own number(0~7). This circuit has two problems. 1. Even if I properly connected 74HC138 with th...