M34E04B Datasheet, PDF (21/35 Pages) STMicroelectronics – 4-Kbit Serial Presence Detect EEPROM compatible

M34E04B
Use within a DDR4 DRAM module
Table 4. Acknowledge when writing data or defining the write-protection status (instructions
with R/W bit = 0)
Status
Instruction
Ack
Address
Ack
Data byte
Ack
Write cycle
(t_W)
Protected
SWPn
NoAck Not significant NoAck Not significant NoAck
No
CWP
Ack Not significant Ack Not significant Ack
Yes
Page or byte write
in protected block
Ack
Address
Ack
Data
NoAck
No
SWPn or CWP
Ack Not significant Ack Not significant Ack
Yes
Not Protected
Page or byte write Ack
Address
Ack
Data
Ack
Yes
Table 5. Acknowledge when reading the protection status (instructions with
R/W bit = 1)
SWPn Status
Instruction
Ack
Address
Ack
Data byte
Ack
Set
RPSn
NoAck Not significant NoAck Not significant NoAck
Not set
RPSn
Ack Not significant NoAck Not significant NoAck
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