1-Wire Digital Thermometer with
Sequence Detect and PIO
DS28EA00
28 Maxim Integrated
1-Wire Communication Examples (continued)
RST
PIO Access Write (Invalid Data Byte)
PD SELECT FF Loop
AA Loop
00 Loop
xx Loop
RST
Change Chain State (Success)
PD SELECT CHAIN
CHAIN
CHAIN
CHAIN
CHAIN
RST
Change Chain State (Transmission Error)
PD SELECT
The PIO Access Write command is ignored by the device while in chain ON or chain DONE state.
RST
Change Chain State (Invalid Control Byte)
PD SELECT
RST PD
<96h> <69h>
<AAh>
<Registration Number>
Wait for chain to charge
Put all devices into
chain ON state.
No response: all devices have
been discovered
Put all devices into chain OFF state.
<AAh>
Identify the first device and
put it into chain DONE state.
Identify the next device and
put it into chain DONE state.
Repeat this sequence until
no device responds.
SKIPR
CDRR
CHAIN
<96h>
<69h>
<Registration Number>
<AAh>
CDRR
RST
Sequence Discovery Example
PD
RST PD
RST PD
<8 Bytes FFh>CDRR
SKIPR
RST PD
PIOW
<PIO Output Data>
<Invalid Data Byte>
<Chain Control Byte>
<Invalid Control Byte> <Inverted Previous Byte>
<Any Byte> <Byte ≠ Inverted Previous Byte>
<Chain Control Byte>
For the sequence discovery to function properly, the logic state at PIOB (EN) must not change during the transmission of
the Conditional Read ROM command code, and, if the device responds, must stay at logic 0 until the entire 64-bit regis-
tration number is transmitted.
μSOP
2 7 PIOBN.C.
18V
DD
IO
PIOAN.C. 3 6
N.C.GND 4 5
DS28EA00
+
Pin Configuration Package Information
For the latest package outline information and land patterns, go
to www.maximintegrated.com/packages
.
PACKAGE TYPE PACKAGE CODE DOCUMENT NO.
8 µSOP U8+1
21-0036
