ST STM32L4+ Series Reference Manual page 567

RM0432
During the read operation, the RWDS is used by the device, in two ways:
•
during the command/address phase, to request an additional latency
•
during the data phase, for data strobing
CS#
CK
RWDS
DQ[7:0]
During the write operation the RWDS is used:
•
By the device, during the command/address phase, to request an additional latency
•
By the OCTOSPI, during the data phase, for write data masking
CS#
CK
RWDS
DQ[7:0]
Figure 76. HyperBus read operation with initial latency
t =Read Write Recovery
RWR
High = 2x Latency Count
Low = 1x Latency Count
47:40 39:32 31:24 23:16
Command-Address
Host drives DQ[7:0] and Memory drives RWDS
Figure 77. HyperBus write operation with initial latency
t
=Read Write Recovery
RWR
High = 2x Latency Count
Low = 1x Latency Count
47:40 39:32 31:24 23:16
Command-Address
Host drives DQ[7:0] and Memory drives RWDS
t = Initial Access
ACC
Latency Count
15:8 7:0
t = Access
ACC
Latency
Count
15:8 7:0
RM0432 Rev 6
Octo-SPI interface (OCTOSPI)
RWDS and Data
are edge aligned
Dn Dn Dn+1
A B A
Memory drives DQ[7:0]
and RWDS
CK and Data
are center aligned
Dn Dn Dn+1 Dn+1
A B A B
Host drives DQ[7:0]
and RWDS
Dn+1
B
MSv43492V1
MSv43494V1
567/2301
603