Using 4fnd (seven segment dispaly) count down from 100 to 0, also buzz once hits 0

I'm trying to have my 4fnd count down from 100 to 0.
once the count has hit zero buzzer sounds.
Currently my code is out putting on my display 1234 then 2345, 3456 and so on, but i just want it to start at 100 and decrement 1 each time with a 200ms delay each time. This is what I have so far..

My main focus is just fixing this loop to make it count from 100 to 0.

#define FND_A 2
#define FND_DP 9
int beepPin = 10;
int pos[4] = {A0,A1,A2,A3};

void setup()
for(int i = FND_A ; i <= 10; i++){
pinMode(i, OUTPUT);
for(int i = 0; i < 4; i++){
pinMode(pos[i], OUTPUT);
boolean digit[10][8] = {
{ 1,1,1,1,1,1,0,0 }, //0
{ 0,1,1,0,0,0,0,0 }, //1
{ 1,1,0,1,1,0,1,0 }, //2
{ 1,1,1,1,0,0,1,0 }, //3
{ 0,1,1,0,0,1,1,0 }, //4
{ 1,0,1,1,0,1,1,0 }, //5
{ 1,0,1,1,1,1,1,0 }, //6
{ 1,1,1,0,0,0,0,1 },
{ 1,1,1,1,1,1,1,1 },
{ 1,1,1,0,0,1,1,0, }
unsigned long pre = 0;
int count = 0;
void loop()
unsigned long current = millis();

if(current - pre > 1000){
  pre = current;
  if(count ==5)
  count = 0;
for(int i = 0; i < 4; i++){
  number(count + i);


void number(int n){
for(int i = FND_A; i <= FND_DP; i++)
digitalWrite(i, digit[n][i - 2]);


void positions(int p){
for(int i =0; i<3; i++){
digitalWrite(pos[i], HIGH);

Please edit your post to add code tags ("</>" editor button).

Do you know how to send a four digit number to the display?

If so, start from there, and count that number down.

I believe i added it, also i trying to change the loop i have in order to count down from 100 to 0, instead of what its currently doing which is starting at 1234 then going to 2345, 3456....

What about the code tags? Reply #2?

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That is certainly a mystery.

Evidently, you don't yet know how to display an arbitrary number. The number 100 might be fun. Don't you think it would be wise to figure out how to do that, then move on to greater things?

Don't forget to add the code tags!

any other help would be appreciated thank you!

i did add the codes, tags I'm just trying to figure out how to make my 4fnd display 100 and count down to 0.

How is that going? Thoughts? Observations? We need some follow up information from reply #6. Before you can count, you certainly must be able to display a number. If you can't, then that is what you should be working on.

ive had something displayed this whole time, im geting 1234 but its going up? and im not sure how to start it at 100.

I could upload a picture of my Arduino if that would help clarify things.

What are you trying to do there?

By the way, where is your schematic or wiring diagram that the forum guidelines ask you to post? As pointed out to you in the links you were directed to, in reply #5.

I believe this checking the position when it's less then 4 and if it is incrementing each number by one.

Believe, but don't know? Did someone else write the code?

I haven't created a schematic for this yet, but i can right now

Please do. Also please read the links that you were directed to.

okay will do, sorry about that!

It looks to me that you did not write this code, which means that to change it, you first need to understand it. To do so, go through it line by line, and make sure you know what each line does, and why.

Or, you could write your own!

We were given this code to work off of.

Well, that is a bummer.

That code is written in a particularly obtuse style that is quite difficult for beginners to understand.

Would there be a problem if you were to write your own, after studying some much more reasonable and simpler approaches?

Here are a couple: