MAX1464 Datasheet, PDF (20/47 Pages) Maxim Integrated Products – Low-Power, Low-Noise Multichannel Sensor Signal Processor

Low-Power, Low-Noise Multichannel
Sensor Signal Processor
CS
SCLK
IRS0
IRS1
DI
IRSA0
IRSA1
Figure 8. Serial Interface Data Input
IRS2
IRSA2
IRS3
IRSA3
IRS4
IRSD0
IRS5
IRSD1
IRS6
IRSD2
IRS7
IRSD3
CS
SCLK
DI
DO
IRS0
IRSA0
DHR15
IRS1
IRSA1
DHR14
IRS2
IRSA2
DHR13
IRS3
IRSA3
DHR12
IRS4
IRSD0
DHR11
IRS5
IRSD1
DHR10
IRS6
IRSD2
DHR9
IRS7
IRSD3
DHR8
IRS0
IRSA0
DHR7
IRS1
IRSA1
DHR6
IRS2
IRSA2
DHR5
IRS3
IRSA3
DHR4
IRS4
IRSD0
DHR3
IRS5
IRSD1
DHR2
IRS6
IRSD2
DHR1
IRS7
IRSD3
DHR0
Figure 9. 4-Wire Mode Data Read from DHR Register
CS
SCLK
DI
10011000
DO
IRSA0 IRSA1 IRSA2 IRSA3 IRSD0 IRSD1 IRSD2 IRSD3
DHR15 DHR14 DHR13 DHR12 DHR11 DHR10 DHR9 DHR8 DHR7 DHR6 DHR5 DHR4 DHR3 DHR2 DHR1 DHR0
Figure 10. 3-Wire Mode Data Read from DHR Register
FLASH Memory
There are 4096 bytes of programmable/erasable FLASH
memory for CPU program instructions and coefficients
storage. In addition, there are 128 bytes of FLASH mem-
ory accessible only by the serial interface for storage of
user information data.
These two FLASH memory locations are separated as
partitions. The program/coefficient memory is FLASH
partition 0 and the information memory is FLASH parti-
tion 1. Each partition is accessible by the serial inter-
face for reading, erasing, and writing data. Program/
coefficient memory partition 0 is accessible by the CPU
as read only, and partition 1 is not accessible by the
CPU. The CPU cannot erase or write data to either of
the FLASH memory partitions.
FLASH partition 0 is selected during the POR cycle.
FLASH partition 1 is selected by sending the halt CPU
command (IRS[7:0] = 78h) and changing the partition
selected by sending the change partition command
(IRS[7:0] = F8h). A following halt command (IRS[7:0] =
78h) resets the selected partition to partition 0.
Modifying the FLASH Contents
The MAX1464 FLASH memory contents must be erased
(contents = FFh) before the desired contents can be writ-
ten. There is no individual byte-erase command, but
either a total-erase command (IRS[7:0] = E8h) where all
the selected partition is erased (4kB for partition 0 or 128
bytes for partition 1) or a page-erase command (IRS[7:0]
= D8h), where only 64 bytes are erased, and the page is
selected by PFAR[11:6]. There are 64 pages in FLASH
partition 0, and only 2 pages in FLASH partition 1.
The programming of the MAX1464 FLASH memory
must use the following procedure (all the commands
are to be sent through the serial interface, and are
hexadecimal values of IRS[7:0]):
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