I need help finishing this program, I am coding this in pep$/9$ assembly language. The output that his program is suppose to give is the user inputs letters of A$,$ B$,$ and C$.$ The program has to remember how many times the user inputs the letter. To end the program, I used the letter X to quit it$.$ I am stuck on trying to make the loop work. This is what I have done so far and I don't know what I am missing.

BR main

countA: $.$WORD $0$

countB: $.$WORD $0$

countC: $.$WORD $0$

letter: $.$WORD $0$

msg: $.$ASCII "Enter a letter A$,$ B$,$ C or X to quit: $\backslash$x$00"$

msgA: $.$ASCII "Number of A$\text{'}$s: $\backslash$x$00"$

msgB: $.$ASCII "Number of B$\text{'}$s: $\backslash$x$00"$

msgC: $.$ASCII "Number of C$\text{'}$s: $\backslash$x$00"$

main: STRO msg$,$d

DECI letter,d

loop: LDWA letter,d

CPWA $\text{'}$X$\text{'},$i

BREQ done

CPWA $\text{'}$A$\text{'},$i

BREQ NOA

CPWA $\text{'}$B$\text{'},$i

BREQ NOB

CPWA $\text{'}$C$\text{'},$i

BREQ NOC

STRO msg$,$d

DECI letter,d

BR loop

NOA: LDWA countA,d

ADDA $1,$i

STWA countA,d

STRO msg$,$d

DECI letter,d

BR loop

NOB: LDWA countB,d

ADDA $1,$i

STWA countB,d

STRO msg$,$d

DECI letter,d

BR loop

NOC: LDWA countC,d

ADDA $1,$i

STWA countC,d

STRO msg$,$d

DECI letter,d

BR loop

done: STRO msgA,d

LDWA countA,d

DECO countA,d

STRO msgB$,$d

LDWA countB,d

DECO countB,d

STRO msgC$,$d

LDWA countC,d

DECO countC,d

STOP

$.$END