Zilog Z16C35 User Manual
Page 209
Application Note
The Z180™ Interfaced with the SCC at MHZ
7-32
(Continued)
db
01h
;select WR1
db
11100000b
;enable DMA
db
0fh
;select WR15
db
00000000b
;don’t use any of ext/stat int
db
10h
;reset ext/stat twice
db
10h
db
01h
;select WR1
db
11100000b
;no int
db
09h
;select WR9
db
00001001b
;enable int
db
0ffh
;end of table
;source/dist addr table for Z180’s dma
addrtab:
db
scc_data
;dmac0 source
db
00h
db
00h
dw
rx_buff
;dmac0 dist
db
00h
dw
length
;byte count
dw
tx_buff+1
;mar
db
00h
db
scc_data
;iar
db
00h
db
00h
;dummy!
dw
length-1
;byte count
;interrupt vector table
org
sccdma + 200h
z180vect:
.block
2
;180 int1 vect 00000
.block
2
;180 int2 vect 00010
.block
2
;180 prt0 vect 00100
.block
2
;180 prt1 vect 00110
dw
rxend
;180 dmac0 vect 01000
dw
txend
;180 dmac1 vect 01010
.block
2
;180 csi/o vect 01100
.block
2
;180 asci0 vect 01110
.block
2
;180 asci1 vect 10000
org
sccdma + 1000h
tx_buff:
.block
length
rx_buff:
.block
length
temp:
.block
1
end
Table 14. Test Program – Z180/SCC DMA Transfer (Continued)
Page 203 of 316
UM011002-0808