Rainbow Electronics DS1972 - Manual (Page 16)

DS1972: 1024-Bit EEPROM iButton
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Figure 9-1. ROM Functions Flow Chart
From Figure 9
2 nd Part
To Memory Functions
Flow Chart (Figure 7)
Master TX Bit 0
Master TX Bit 63
Master TX Bit 1
Bit 63
Match ?
RC = 0
DS1972 TX Bit 0
DS1972 TX Bit 0
Master TX Bit 0
DS1972 TX Bit 1
DS1972 TX Bit 1
Master TX Bit 1
DS1972 TX Bit 63
DS1972 TX Bit 63
Master TX Bit 63
RC = 1
Bit 1
Match ?
Bit 0
Match ?
Y
N
Y
N
Y
N
Bit 63
Match ?
RC = 0
RC = 1
Bit 1
Match ?
Bit 0
Match ?
Y
N
Y
N
Y
N
RC = 0
DS1972 TX
CRC Byte
DS1972 TX
Serial Number
(6 Bytes)
DS1972 TX
Family Code
(1 Byte)
RC = 0
To Figure 9
2 nd Part N F0h
Search ROM
Command ?
N 55h
Match ROM
Command ? N
CCh
Skip ROM
Command ?
Y Y Y Y
N 33h
Read ROM
Command ?
To Figure 9
2 nd Part
From Memory Functions
Flow Chart (Figure 7)
Bus Master TX ROM
Function Command
DS1972 TX
Presence Pulse
OD
Reset Pulse ?
N
Y
OD = 0
Bus Master TX
Reset Pulse
From Figure 9, 2 nd Part