DS2465 MAXIM [Maxim Integrated Products], DS2465 Datasheet - Page 11

• Manufacturer Part Number: DS2465
• Description: SHA-256 Coprocessor with 1-Wire Master Function
• Manufacturer: MAXIM [Maxim Integrated Products]

Figure 4. Rising Edge Pullup During a Time Slot
The DS2465 allows adapting several timing parameters and the pullup resistor to the application’s needs. Each of these
parameters has its own 1-Wire Port Configuration register, located in the address range from 68h to 6Dh
t
to standard speed, the upper nibble to overdrive speed. The t
parameter t
the upper nibble has no function. See
After a device reset (power-up cycle, a low pulse at SLPZ, or initiated by the 1-Wire Master Reset command), the 1-Wire
Port Configuration registers are initialized to their default values. To change a port configuration, access the respective
register in I
be adjusted in a single write access. The new setting applies on the rising SCL edge of the data byte acknowledge bit,
provided that the 1-Wire line is not busy (1WB = 0). The upper 4 bits of the registers at 6Bh to 6Dh are not used. They
can be written, byte their value has no effect on the device operation.
Table 5. 1-Wire Port Configuration Address Details
RSTL
SHA-256 Coprocessor with 1-Wire Master Function
ADDRESS
6Ch
6Dh
6Ah
6Bh
68h
69h
, t
MSP
W1L
2
and t
C write mode and provide the new code as data byte. Starting at address 68h all port configurations can
can be adjusted for overdrive speed only; the standard speed value us fixed. For t
W0L
BIT 7
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the values for standard and overdrive speed can be adjusted independently. The lower nibble applies
V
V
V
0V
t
CC
IAPO
IL1MAX
1-Wire LINE IS
DISCHARGED
t
t
RSTL
MSP
W0L
(not used, default 0000b)
(not used, default 0000b)
(not used, default 0000b)
BIT 6
Overdrive Speed (OD)
Overdrive Speed (OD)
Overdrive Speed (OD)
Table 6
APU = 1
t
1
BIT 5
for the conversion between binary code and parameter value.
t
2
BIT 4
t
REC0
REC0
and R
t
3
BIT 3
WPU
APU = 0
settings apply at both 1-Wire speeds. The
t
t
t
R
t
RSTL
t
MSP
W0L
W1L
REC0
WPU
BIT 2
Standard Speed (STD)
Standard Speed (STD)
Overdrive Speed (OD)
1-Wire Port Configurations
Standard Speed (STD)
(speed independent)
(speed independent)
BIT 1
REC0
DS2465
, R
WPU
(Table
and t
BIT 0
5). For
W1L