MAX1441 Datasheet, PDF (31/41 Pages) Maxim Integrated Products – Automotive, Two-Channel Proximity and Touch Sensor

Automotive, Two-Channel Proximity and
Touch Sensor
Memory Organization
There are three distinct memory areas in the IC's regis-
ters, program memory, and data memory. All memories
are located on-chip.
Data memory is realized by SRAM memory, which allows
both read and write access; program memory is imple-
mented with nonvolatile Flash memory. The user applica-
tion codes are programmed using a bootstrap loader.
The bootstrap loader program is located in the utility code
space. From a user perspective, the utility code segment
is a program segment in the program memory map.
As illustrated in Figure 3, the device incorporates 4KB
program memory, 4KB Utility ROM, and 128 bytes SRAM
data memory.
Data memory is contiguous from 0000h to 03Fh words.
Programmable memory begins at address 0000h and is
contiguous through a maximum of 7FFh words.
The device also incorporates a soft stack using data
RAM for the stack.
The MMU provides access controls for program and
data memories. The built-in bootstrap loader is used to
support Flash memory erase/program operations.
Register Space
Two of the register modules (M0/M1) are used by the
device.
Data Memory
On-chip data memory begins at address 0000h and is
contiguous through the internal data memory space to
03Fh words (128 bytes).
Data memory mapping and access control are handled
by the MMU. Read/write access to the data memory can
be in word or in byte.
Program Memory
The program memory is implemented using nonvola-
tile Flash memory. Flash memory provides in-system
programming capability but this memory technology
requires erase operation before a write operation and the
time required to carry out write access is extremely long.
Write access to nonvolatile memory is actually performed
by utility ROM code for the device.
REGISTERS _FFh
1Fh
0Fh
SPRs
FFFFh
WBSn = 1
FFFFh
WBSn = 0
FFFFh
PROGRAM
SPACE
87FFh
2K x 16
UTILITY CODE
8000h
DATA
SPACE
07h
06h
SFRs
00h
Figure 3. Memory Map
07FFh
0000h
2K x 16
PROGRAM
MEMORY
003Fh
0000h
64 x 16
DATA RAM
007Fh
0000h
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