# C166 Processor

Assembler code

```
ROM:00005920
ROM:00005920 ; =============== S U B R O U T I N E =======================================
ROM:00005920
ROM:00005920
ROM:00005920 sub_5920:                               ; CODE XREF: ROM:00005A1A↓P
ROM:00005920                                         ; ROM:00005ADC↓P
ROM:00005920                 mov     r4, r8
ROM:00005922                 cmpb    rl4, #0
ROM:00005924                 jmpr    cc_NZ, loc_5932
ROM:00005926                 mov     r5, #4
ROM:00005928                 or      dword_18+4, ZEROS
ROM:0000592C                 or      dword_18+6, r5
ROM:00005930                 jmpr    cc_UC, loc_593E
ROM:00005932 ; ---------------------------------------------------------------------------
ROM:00005932
ROM:00005932 loc_5932:                               ; CODE XREF: sub_5920+4↑j
ROM:00005932                 mov     r5, #0FFFBh
ROM:00005936                 and     dword_18+4, ONES
ROM:0000593A                 and     dword_18+6, r5
ROM:0000593E
ROM:0000593E loc_593E:                               ; CODE XREF: sub_5920+10↑j
ROM:0000593E                 mov     r4, r9
ROM:00005940                 cmpb    rl4, #0
ROM:00005942                 jmpr    cc_NZ, loc_5950
ROM:00005944                 mov     r5, #8
ROM:00005946                 or      dword_18+4, ZEROS
ROM:0000594A                 or      dword_18+6, r5
ROM:0000594E                 jmpr    cc_UC, loc_595C
ROM:00005950 ; ---------------------------------------------------------------------------
ROM:00005950
ROM:00005950 loc_5950:                               ; CODE XREF: sub_5920+22↑j
ROM:00005950                 mov     r5, #0FFF7h
ROM:00005954                 and     dword_18+4, ONES
ROM:00005958                 and     dword_18+6, r5
ROM:0000595C
ROM:0000595C loc_595C:                               ; CODE XREF: sub_5920+2E↑j
ROM:0000595C                 mov     r4, dword_18+4
```


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