Intel MB875 - Manual (Page 62)

APPENDIX
58 MB890 User’s Manual
; Name : Read_Reg
; IN : CL - register index
; OUT : AL - Value to read
;[]=================================================
==
Read_Reg Proc Near
Mov
al, cl
mov dx, 4Eh
out dx, al
inc dx
in al, dx
ret
Read_Reg Endp
;[]================================================