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Having error, cant figure out why T.T
Everything was fine but suddenly ~
void get_char ()
{
unsigned int count;
unsigned int x = 0;
unsigned int s_idx = 0;
unsigned int t_idx;
while(msg[x] != '\0') // continue to collect each char from msg[] till the last element
{
t_idx = msg[x]...
Ops, my bad. Yeah there are not the same, was talking bout sinking current part.
I tried to look for capability of 74HC238 (newer version of ls138) on sinking current. Each LED going to have 15mA, so worst case for me is 15mA * 32 = 480mA.
Is 74HC238 able to handle that?
I dont quite...
Hi Zuisti,
Thanks for replying and the time you spent on this. Really appreciate it. The simulation really helps alot!
I am so grateful that being far in the east side of the globe and still I received your help !
I can see that the hardware is similar but I found a minor difference, not sure...
Hi guys,
Need some help over here. I search through some entries but not much mentioning about C and how the display and shifting works. (I am very bad at C T.T)
This is my schematics:
* common cathode block
* I orient it in such a way that the cathode column now become row for scanning...
Hi all,
I am working on a LED Dot Matrix Display and this is my schematics.
I am looking through the programming now and I have a question: how can we output a string of serial bit into shift register (DS) from an array made up of few sets of hex?
For instance:
**broken link removed**
*...
but with insufficient current, even extending the lights up duration it wont help right ?
or you are putting more current through it ? cause I read somewhere that by putting more current (>20mA per LED), it will helps on intensity.
the reason why it wont burn is because it will only lights up...
Since I have the Philips one already is there a need for me get the 74HC138? I think they both do the same job right ?
Can you talk a little bit regarding the intensity of the LED in the group (I joined it !!) ? Most of the references I got outside are about utilizing current sinker like...
sorry matthai but I dont quite get you.
-> Multiplex each LED ? but all LEDs are either connected in row or column. or you mean connecting multiple pins to single row / column but this might burn the LED if there is on 1 or few (which required lesser current) lights up !
-> I havent gone into...
Hi matthai, thanks for your reply. Think I am going put this up and try it out.
I have some questions though:
-> Shift Register:
* you send a 0 to the LED that wish to be lighted up? (and a 1 to anode right?)
-> Fan-out current:
* the current for each LED (the one I am having) is...
Hi folks, I am doing a LED scrolling message board and need some help over here.
After searching here and there, I still have some doubts that need some further explanation.
Basically the schematic are similar.
References:
https://www.edaboard.com/threads/11364/...
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