We are running a survey to help us improve the experience for all of our members. If you see the survey appear, please take the time to tell us about your experience if you can.
Hi,
There are 4 Columns and 16 Rows of LED Matrix.
I have circuit with Philips microcontroller with Port0 and Port1 connected to ULN2003 to Rows of the LED Matrix. While Port 2.2 to Port 2.7 (6 pins) are connected to 74LS245 buffer. The output of this buffer (Pin 11, 12 and 13) are connected to STCP, SHCP and DS Pin of 74HC595 shift register which is connected further to columns of the LED Matrix.
I can choose one row at a time, ON it by keeping all other rows OFF, and then want to ON the entire column. Can someone help me with some sample code to communicate 74LS245 and 74HC595 shift register through the microcontroller?
Regards RS.
So why are you connecting 4 with 5 and 8 with 9?
Do you feel that the poor little LS245 don't have enough juice to feed the other side from a single pin? Next thing is that if the DIR pin is switched, you will get multiple outputs connected together which is not a good idea.
Why are you using a 245 if you don't want dual direction? There are one-direction variants that have all inputs on one side and all outputs on the other side. LS541 would be a more natural choice. And why LS? Why not the HC/HCT family?
Thanks Per. Actually the present circuit is working perfectly with software developed by another engineer. I am not much aware of the hardware part. I have been asked to developed a new software for the same microcontroller from scratch for the same circuit. So I am not able to reply the questions that you asked. I am looking for some help to start with this LS245 and HC595. Better I will scan and upload the circuit diagram here.