DS4830 User’s Guide
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25.4 – Utility ROM Examples
25.4.1 – Reading Constant Word Data from Flash
UROM_moveDP0inc equ 08483h
move DPC, #1Ch ; Set all pointers to word mode
move DP[0], #(table + 8000h) ; Point to address of data as viewed
in the Utility ROM memory map
lcall #UROM_moveDP0inc
move A[0], GR ;
A[0] = 1111h
lcall #UROM_moveDP0inc
move A[1], GR ; A[1] = 2222h
lcall #UROM_moveDP0inc
move A[2], GR ;
A[0] = 3333h
lcall #UROM_moveDP0inc
move A[3], GR ; A[1] = 4444h
sjump $
org 0100h
table:
dw 1111h, 2222h, 3333h, 4444h
25.4.2 – Reading Constant Byte Data from Flash (Indirect Function Call)
INDX_moveDP0inc equ 4
move DPC, #1Ch ; Set all pointers to word mode
move DP[0], #800Dh ; Fetch location of function table from Utility ROM
move BP, @DP[0] ; Set base pointer to function table location
move Offs, #INDX_moveDP0inc ; Set offset to moveDP0inc entry in table
move A[7], @BP[Offs] ; Get address of moveDP0inc function
move DPC, #00h ; Set all pointers to byte mode
move DP[0], #((table * 2) + 8000h) ; Point to address of data as viewed in the Utility ROM memory map and convert
; to byte mode pointer
lcall A[7] ; moveDP0inc
move A[0], GR ; A[0] = 34h
lcall A[7] ; moveDP0inc
move A[1], GR ; A[1] = 12h
lcall A[7] ; moveDP0inc
move A[2], GR ; A[2] = 78h
lcall A[7] ; moveDP0inc
move A[3], GR ; A[3] = 56h
sjump $
org 0100h
table:
dw 1234h, 5678h
