DS3930 Maxim Integrated Products, DS3930 Datasheet - Page 8

• Manufacturer Part Number: DS3930
• Description: DS3930 Hex Nonvolatile Potentiometer With I/o And Memory
• Manufacturer: Maxim Integrated Products

The I/O pins can be used as general-purpose digital
I/O signals. The I/O pins have CMOS outputs with an
Table 2. Memory Map
Hex Nonvolatile Potentiometer with
I/O and Memory
8
Table 1. I/O Pin Truth Table
PULLUP CTRL
(I/O CONTROL
(BITS 7 TO 4)
ADDRESS
00h to 3Fh
40h to EFh
F8h to FFh
REGISTER)
______________________________________________________________________
F0h
F1h
F2h
F3h
F4h
F5h
F6h
F7h
0
0
1
1
I/O PIN SETTING
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
BIT
(I/O CONTROL
(BITS 3 TO 0)
REGISTER)
0
1
0
1
DEFAULT (HEX)
Pullup disabled (HI-Z)
I/O PIN OUTPUT
0X
FF
FF
FF
FF
FF
FF
FF
FF
0F
FF
I/O Signals
0
1
0
Set to 0 to enable I/O
Set to 0 to enable I/O
Set to 0 to enable I/O
Set to 0 to enable I/O
internal pullup resistor (see Figure 2). The I/O pins are
configured with the I/O Control register (F6h) and moni-
tored with the I/O State register (F7h). The I/O Control
register controls the state of the internal pullup resistor
(R
to 0 (see Table 1). The read-only values of the I/O State
register contains the values of the I/O pin setting bits of
the I/O Control register unless the I/O output is tri-stat-
ed. When the I/O is tri-stated the I/O State register will
read high or low depending on the external source on
the I/O pin. Since the I/O pins are controlled by EEP-
ROM, the number of writes is limited.
The memory map is shown in Table 2.
I/O
) with bits 7 to 4 and the I/O pin setting with bits 3
64 bytes of general-purpose EEPROM
Contains state of I/O
Contains state of I/O
Contains state of I/O
Contains state of I/O
Controls potentiometer 0
Controls potentiometer 1
Controls potentiometer 2
Controls potentiometer 3
Controls potentiometer 4
Controls potentiometer 5
Sets I/O
Sets I/O
Sets I/O
Sets I/O
3
2
1
0
FUNCTION
I/O Control
Reserved
Reserved
pullup, set to 1 to disable pullup
pullup, set to 1 to disable pullup
pullup, set to 1 to disable pullup
pullup, set to 1 to disable pullup
I/O State
3
2
1
0
0
0
0
0
to 0 or 1
to 0 or 1
to 0 or 1
to 0 or 1
3
2
1
0
pin (read only)
pin (read only)
pin (read only)
pin (read only)
Memory