mirror of
https://github.com/mgcaret/of816.git
synced 2024-05-28 14:41:27 +00:00
Neon816: VDC access words
This commit is contained in:
parent
bdcbfb2766
commit
343dd83cdd
|
@ -91,7 +91,7 @@ SPI2ctrl3 = $10001F ; init = $05
|
||||||
; VDC
|
; VDC
|
||||||
; *****************
|
; *****************
|
||||||
|
|
||||||
VDCio = $100120 ; read: 1 byte, write: 1 or 2 bytes
|
VDCbase = $100120 ; base address, there are $20 registers
|
||||||
|
|
||||||
; *****************
|
; *****************
|
||||||
; FDC
|
; FDC
|
||||||
|
|
|
@ -209,6 +209,54 @@ dword I2C2_FETCH,"I2C2@+"
|
||||||
.a16
|
.a16
|
||||||
eword
|
eword
|
||||||
|
|
||||||
|
dword VDC_C_STORE,"VDCC!"
|
||||||
|
jsr _popay ; pop offset
|
||||||
|
phy ; save low word
|
||||||
|
jsr _popay ; pop value to write
|
||||||
|
pla ; get offset back
|
||||||
|
phx ; save SP
|
||||||
|
tax ; offset to x reg
|
||||||
|
sep #SHORT_A ; whew! that was fun!
|
||||||
|
.a8
|
||||||
|
tya ; value to A
|
||||||
|
sta f:VDCbase,x
|
||||||
|
rep #SHORT_A
|
||||||
|
.a16
|
||||||
|
plx ; restore SP
|
||||||
|
NEXT
|
||||||
|
eword
|
||||||
|
|
||||||
|
dword VDC_C_FETCH,"VDCC@"
|
||||||
|
jsr _popay ; pop offet
|
||||||
|
phx ; save SP
|
||||||
|
tya
|
||||||
|
tax
|
||||||
|
sep #SHORT_A ; whew! that was fun!
|
||||||
|
.a8
|
||||||
|
lda f:VDCbase,x
|
||||||
|
rep #SHORT_A
|
||||||
|
.a16
|
||||||
|
plx ; restore SP
|
||||||
|
and #$00FF
|
||||||
|
tay
|
||||||
|
lda #$0000
|
||||||
|
PUSHNEXT
|
||||||
|
eword
|
||||||
|
|
||||||
|
dword VDC_STORE,"VDC!"
|
||||||
|
jsr _popay ; again! again! again!
|
||||||
|
phy
|
||||||
|
jsr _popay
|
||||||
|
pla
|
||||||
|
phx
|
||||||
|
tax
|
||||||
|
tya
|
||||||
|
sta f:VDCbase,x
|
||||||
|
rep #SHORT_A
|
||||||
|
.a16
|
||||||
|
plx ; restore SP
|
||||||
|
NEXT
|
||||||
|
eword
|
||||||
|
|
||||||
dend
|
dend
|
||||||
|
|
||||||
|
|
Loading…
Reference in New Issue
Block a user