Sum a byte array to ax register

Question

I have a question about summing one-byte array to ax, this is my code:

IDEAL
MODEL small
STACK 100h
DATASEG
; --------------------------
    arr db 6 dup (200)
; --------------------------
CODESEG
start:
    mov ax, @data
    mov ds, ax
; --------------------------
    xor ax, ax
    add ax, [arr]
    add ax, [arr + 1]
    add ax, [arr + 2]
    add ax, [arr + 3]
    add ax, [arr + 4]
    add ax, [arr + 5]
; --------------------------

exit:
    mov ax, 4c00h
    int 21h
END start

The assembler returns "Operand types do not match" I'm new to assembly so how can I overcome that? Thanks

Answer 1

Eventually I did this to solve my problem:

IDEAL
MODEL small
STACK 100h
DATASEG
; --------------------------
    arr db 6 dup (200)
; --------------------------
CODESEG
start:
    mov ax, @data
    mov ds, ax
; --------------------------
    xor ax, ax
    xor bh, bh
    mov bl, [arr]
    add ax, bx
    mov bl, [arr + 1]
    add ax, bx
    mov bl, [arr + 2]
    add ax, bx
    mov bl, [arr + 3]
    add ax, bx
    mov bl, [arr + 4]
    add ax, bx
    mov bl, [arr + 5]
    add ax, bx
; --------------------------

exit:
    mov ax, 4c00h
    int 21h
END start