WMS7201050M WINBOND [Winbond], WMS7201050M Datasheet - Page 16

• Manufacturer Part Number: WMS7201050M
• Description: 256-TAP QUAD-CHANNEL NON-VOLATILE DIGITAL POTENTIOMETER
• Manufacturer: WINBOND [Winbond]

Inst.
No
12
5
7
Inst.
No.
3
8
9
6
The value stored in the NVMEM location is 9 bits, the 8 bits (D7-D0) of the tap register plus 1 bit (D8)
of the output buffer mode. The NVMEM position must be erased before writing to it. There are two
ways to program a value into NVMEM.
Write a value directly from the microcontroller
Load the current potentiometer setting into NVMEM.
For programming NVMEM, the following sequence must be followed:
Command
Name
Erase
NVMEM
Program
NVMEM
Program
NVMEM with
Tap Register
1. Erase word at NVMEM location
2. Program word at NVMEM location
Command
Name:
Write to
Tap
Register
Up
Down
Load Tap
Register
7.8.4 Programming
Command Byte
1 1 0 1 A3 A2 A1 A0
0 0 1 0 A3 A2 A1 A0
0 0 1 1 A3 A2 A1 A0
0 1 1 1 x x A1 A0
Command Byte
0 1 0 0 x x A1 A0
1 1 1 1 x x A1 A0
1 0 1 1 A3 A2 A1 A0
TABLE 7 – WRITING TO THE TAP REGISTERS
Non-Volatile
TABLE 8 – PROGRAMMING NVMEM
Data Byte 1
Data Byte 1
x x x x x x x x
x x x x x x x x
x x x x x x x x
x x x x x x x x
x x x x x x x x
x x x x x x x D8
x x x x x x x x
Memory (NVMEM)
- 16 -
Data Byte 2
D7 D6 D5 D4 D3 D2 D1 D0
Data Byte 2
D7 D6 D5 D4 D3 D2 D1 D0
x x x x x x x x
x x x x x x x x
x x x x x x x x
x x x x x x x x
x x x x x x x x
WMS7204
Comment
Writes a value to
the tap register of
the selected
channel
Increment tap
register value by
one
Decrement tap
register value by
one
Load the selected
NVMEM location
into the tap
register
Comment
word pointed to by
A3, A2, A1 and A0.
Writes a value to
the selected
NVMEM register of
the selected
channel
Takes the current
potentiometer
settings and saves
in the selected
NVMEM location.
Erases the 9 bit