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©2018 Integrated Device Technology, Inc
September 12, 2018
8A3xxxx Family Programming Guide
SPI burst mode operation is required to ensure data integrity of multi-byte registers. When accessing a multi-byte register, all data bytes must
be written or read in a single SPI burst access. Bursts may be of greater length if desired, but must not extend beyond the end of the register
page. An internal address pointer is incremented automatically as each data byte is written or read.
SPI 1-byte (1B) Addressing Example
Example Write to “50” to register 0xCBE4
7C 80 CB 10 20
#Set Page register
64* 50
#*MSB is 0 for write transactions
Example Read from 0xC024:
7C 00 C0 10 20
#Set Page register
A4* 00
#*MSB is set, so this is a read command
SPI 2-byte (2B) Addressing Example
Example Write to “50” to register 0xCBE4
7F FD 80 10 20
#Set Page register
4B E4* 50
#*MSB is 0 for write transactions
Example Read from 0xC024:
7F FD 80 10 20
#Set Page register
C0* 24 00
#*MSB is set, so this is a read command
Table 5: SPI 2B Mode Page Register Bit Field Locations and Descriptions
Offset
Address
(Hex)
SPI 2B Mode Page Register Bit Field Locations
D7
D6
D5
D4
D3
D2
D1
D0
7FFD
1
PAGE_ADDR
[15]
PAGE_ADDR[14:8]
7FFE
PAGE_ADDR[23:16]
7FFF
PAGE_ADDR[31:24]
1. Burst access must begin at this non-aligned offset and all 3 bytes must be written in the same SPI burst access. A burst beginning at the
32-bit aligned address of 7FFCh will not correctly set this register.
SPI 2B Mode Page Register
Bit Field Descriptions
Bit Field Name
Field Type Default Value
Description
PAGE_ADDR[14:8]
R/W
0000000b
The values in this field are always replaced by the bits in SPI transaction itself
and so have no meaning.
PAGE_ADDR[15]
R/W
0b
Select which register page to access. Forms the most-significant bit of the 16-bit
register address. Only a value of 1b should be used. Lower addresses are not
user-accessible
PAGE_ADDR[23:16]
R/W
10h
Must be set to 10h in all cases
PAGE_ADDR[31:24]
R/W
20h
Must be set to 20h in all cases