PSD4235G2V_09 datasheet(13/124 Pages) STMICROELECTRONICS

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PSD4235G2V

Description

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1.2.1

Simultaneous READ and WRITE to Flash memory

How can the MCU program the same memory from which it executing code? It cannot. The

PSD allows the MCU to operate the two Flash memory blocks concurrently, reading code

from one while erasing and programming the other during IAP.

1.2.2

Complex memory mapping

How can I map these two memories efficiently? A programmable Decode PLD (DPLD) is

embedded in the PSD. The concurrent PSD memories can be mapped anywhere in MCU

address space, segment by segment with extremely high address resolution. As an option,

the secondary Flash memory can be swapped out of the system memory map when IAP is

complete. A built-in page register breaks the MCU address limit.

1.2.3

Separate Program and Data space

How can I write to Flash memory while it resides in Program space during field firmware

updates? My 80C51XA will not allow it. The PSD provides means to reclassify Flash

memory as Data space during IAP, then back to Program space when complete.

1.3

PSDsoft™ Express

PSDsoft Express, a software development tool from ST, guides you through the design

process step-by-step making it possible to complete an embedded MCU design capable of

ISP/IAP in just hours. Select your MCU and PSDsoft Express takes you through the

remainder of the design with point and click entry, covering PSD selection, pin definitions,

programmable logic inputs and outputs, MCU memory map definition, ANSI-C code

generation for your MCU, and merging your MCU firmware with the PSD design. When

complete, two different device programmers are supported directly from PSDsoft Express:

FlashLINK (JTAG) and PSDpro.

PSD4235G2V Datasheet(PDF) 13 Page - STMicroelectronics