Could RSI value show most update value on eur/usd chart?

Hello, Folks
I just wrote the EA code which for show the rsi(M30) onto the eur/usd chart screen, in order to save more space on the chart. The code as below:

double rsi=iRSI(NULL,PERIOD_M30,14,PRICE_MEDIAN,0);
Comment("RSI: ",DoubleToStr(rsi,0));

However, if I drag the normal rsi indicator onto the chart, the rsi value is real time to update the latest value when the pip up or down. But my above code on the chart, it is only refresh the rsi value when new M30 bar is starting to run. Do I miss something to cause it cannot update like as the normal rsi indicator? Or my method cannot achieve it?

Could you kindly advise me how to get most update rsi value onto the chart? Much thanks!

There is no problem with the code that you posted. The problem is with some of the other logic. I could take a guess but that isn't much use. You have to look at the logic that controls how data is processed. Specifically does it process every tick or just when a new bar forms.

Thanks for your advise. I have no any code to control the tick or bar.
Any idea that my rsi value and comment on chart can refresh every 1 min automatically?

I guess iRSI is using PRICE_CLOSE.

I mean
double rsi=iRSI(NULL,PERIOD_M30,14,PRICE_CLOSE,0);

No. I am using double rsi=iRSI(NULL,PERIOD_M30,14,PRICE_MEDIAN,0);
But I think the problem is not from price type...but I have no idea why cannot real time update the rsi value like as the drag indicator onto the chart.

there are 2 causes why your RSI value on screen seems doesn't refresh
1. price_median is calculated as (high+low)/2. when a new bar is forming on the screen, as long as the last tick is between the high and the low of the current bar, price_median value will not change.
2. by using DoubleToStr(rsi,0), you truncated the decimal point of rsi. if rsi value change between 45.0 to 45.9, value displayed on screen will always be 45. here you say it doesn't refresh. try using DoubleToStr(rsi,1)

hope this help