X9251 Datasheet, PDF (11/22 Pages) Xicor Inc. – Quad Digitally-Controlled (XDCP) Potentiometer

X9251
INSTRUCTION FORMAT
Read Wiper Counter Register (WCR)
CS
Falling
Edge
Device Type
Identifier
0101
Device
Addresses
0 0 A1 A0
Instruction
Opcode
1001
WCR
Addresses
00 0 0
Wiper Position
(Sent by X9251 on SO)
CS
W ^W W W W W W W _Rising
C ^C C C C C C C _Edge
RRRRRRRR
76543210
Write Wiper Counter Register (WCR)
CS
Falling
Edge
Device Type
Identifier
0101
Device
Addresses
0 0 A1 A0
Instruction
Opcode
1010
WCR
Addresses
00 0 0
Data Byte
(Sent by Host on SI)
CS
W ^W W W W W W W _Rising
C ^C C C C C C C _Edge
RRRRRRRR
76543210
Read Data Register (DR)
Device Type Device
Instruction DR and WCR
Data Byte
CS
Identifier
Addresses
Opcode
Addresses
(Sent by X9271 on SO) ^CS
Falling
Rising
Edge
0
1
0
1
0
0
A1 A0
1
0
1
1
RB RA P1
P0
DDDDDDDD
76543210
Edge
Write Data Register (DR)
Device Type Device Instruction DR and WCR
Data Byte
Identifier Addresses Opcode
CS
Addresses
(Sent by Host on SI)
CS
Falling
Rising
Edge
0
1
0
1
0
0 A1 A0
1
1
0
0
RB RA P1
P0
DDDDDDDD
76543210
Edge
Global Transfer Data Register (DR) to Wiper Counter Register (WCR)
CS ^{Device Type}
Device
Instruction
DR
CS
Falling ^Identifier
Addresses
Opcode
Addresses _Rising
Edge _{0 1 0 1 0 0 A1 A0 0 0 0 1 RB RA 0 0} Edge
Notes: (1) “A1 ~ A0”: stands for the device addresses sent by the master.
(2) WPx refers to wiper position data in the Counter Register
(2) “I”: stands for the increment operation, SI held HIGH during active SCK phase (high).
(3) “D”: stands for the decrement operation, SI held LOW during active SCK phase (high).
11
FN8166.2
September 14, 2005