AN3478| Application Note
Maxim/Dallas > App Notes > MICROCONTROLLERS Keywords: flash memory, ROM, TINI, DS80C400, DS80C410, DS80C411, flash, program, erase, app note 3478
Feb 23, 2005
APPLICATION NOTE 3478
DS80C400/410/411 Flash Memory Selection
Abstract: The DS80C400/DS80C410/DS80C411 networked microcontrollers have specific electrical and timing requirements that must be met for a flash memory chip to be compatible. This application note describes those requirements and gives examples of memory chips that are fully compatible with the DS80C400/DS80C410/ DS80C411. Software code is presented that can be used to erase and program flash memory that is electrically compatible, but not ROM-loader software compatible. After reading this application note, customers should be able to determine which flash memories to use on DS80C400/DS80C410/DS80C411 designs.
Overview
This application note describes the compatibility requirements for flash memory used with the DS80C400/ DS80C410/DS80C411 networked microcontrollers. Examples of fully compatible flash-memory chips will be given. This note also presents software that can be used to erase and program flash memory that is electrically compatible, but not ROM-loader software compatible. All program code referenced in this application note is available for download from the Dallas Semiconductor ftp server.
Requirements
To work with the DS80C400/DS80C410/DS80C411, a flash memory chip must be electrically compatible and it must meet defined timing requirements (i.e., be fast enough).
Electrical
The DS80C400/DS80C410/DS80C411 require 3.3V byte-wide (x 8) flash memory.
Access Time
The DS80C400/DS80C410/DS80C411 execution speed (CPU speed) is the crystal speed, times the clock multiplier. (The clock multiplier is not touched by the ROM loader, but can be set by application software.) The clock period tclcl is calculated as 1/(CPU speed). Execution out of flash is only possible when the flash memory meets the DS80C400/DS80C410/DS80C411 timing requirements, as listed in the respective data sheets. Table 1 shows examples of execution speeds for the DS80C400 and the AM29LV081 flash.
AN3478 Application Note maxim Download PDF
Add this permalink to your bookmarks for future download of AN3478 ApplicationNote
Permalink: http://application.emcelettronica.com/maxim/AN3478
