Datasheet

LTC1096/LTC1096L
LTC1098/LTC1098L
26
10968fc
TYPICAL APPLICATIONS
MPU TRANSMIT
WORD
CS
CLK
D
OUT
MPU RECEIVED
WORD
D
IN
0001
ODD/
SIGN
MSBF
X
SGL/
DIFF
XXXXXXXX
START
BIT
BYTE 1 BYTE 2 (DUMMY)
X = DON'T CARE
START
SGL/
DIFF
DON'T CARE
B7 B6 B5 B4 B3 B2 B1 B0
ODD/
SIGN
MSBF
???????0
B7 B6 B5 B4 B3 B2 B1 B0
2ND TRANSFER1ST TRANSFER
10968 TA03
10968 TA04
CLK
D
IN
CS
ANALOG
INPUTS
C0
SCK
D
OUT
MISO
MOSI
MC68HC05C4
LTC1098
LOCATION A + 1
LSB
LOCATION A
BYTE 2
BYTE 1
10968 TA05
B7 B6 B5 B4 B3 B2 B1 B0
00000000
Data Exchange Between LTC1098(L) and MC68HC05C4
Hardware and Software Interface to Motorola MC68HC05C4
D
OUT
from LTC1098(L) Stored in MC68HC05C4
LABEL MNEMONIC COMMENTS
START BCLRn
LDA
STA
TST
BPL
LDA
STA
AND
STA
TST
BPL
BSETn
LDA
STA
Bit 0 Port C goes low (CS goes low)
Load LTC1098(L) D
IN
word into Acc.
Load LTC1098(L) D
IN
word into SPI from Acc.
Transfer begins.
Test status of SPIF
Loop to previous instruction if not done
with transfer
Load contents of SPI data register
into Acc. (D
OUT
MSBs)
Start next SPI cycle
Clear the fi rst D
OUT
word
Store in memory location A (MSBs)
Test status of SPIF
Loop to previous instruction if not done
with transfer
Set B0 of Port C (CS goes high)
Load contents of SPI data register into
Acc. (D
OUT
LSBs)
Store in memory location A + 1 (LSBs)