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try to reverse some algo in c167 arch. in a part of the file i saw a variable that located in XRAM mov to accumulator registers and finally xor with other registers. as below:

mov     r1, word_E1C4
mov     r2, word_E1C6
cpl     r1
cpl     r2
xor     r12, r1
xor     r13, r2

i guess this value (word_E1C4 and word_E1C6) create the required constant value for my algorithm. so i search this values in firmware file and i found this instructions :

mov     r4, #0
mov     r5, #0Fh
calls   0Fh, 428Ch ; 0F428Ch
mov     word_E1C4, r10
mov     word_E1C6, r11

so it seems r10 and r11 have the constant value inside them and these values are created in calls 0Fh, 428Ch ; 0F428Ch !!!! But what is Calls instruction? this instruction refer to incorrect address How can I find these values? any body can help me about this ?

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