Why and when flash memory is needed in embedded system?

Started by John in comp.arch.embedded13 years ago 39 replies

Is it possible that embedded system doesn't have flash memory? If we use flash memory in embedded system, then we don't need to use ROM,...

Is it possible that embedded system doesn't have flash memory? If we use flash memory in embedded system, then we don't need to use ROM, or both? My understanding is that flash memory is similar to ROM, that stores permanent data like boot up instructions?? Is that correct? Please advice. thanks...


Software development for MicroBlaze

Started by Steve in comp.arch.embedded13 years ago 1 reply

I'm writing a software for microblaze soft processor (Spartan 3E Starter Kit) and I have a few questions regarding the using of memory. The...

I'm writing a software for microblaze soft processor (Spartan 3E Starter Kit) and I have a few questions regarding the using of memory. The first question is where my code is running? The starter kit has an external 64MB DDR memory and internal local memory (Use BRAM). When I download the bit stream to the FPGA, where is the program running? It seems it is running in the local memory. ...


How to read/write an 'address' from a memory location......

Started by Anonymous in comp.arch.embedded12 years ago 18 replies

I am trying to read an address from a memory location and then write into that memory location. i.e. unsigned long * mem_pointer =...

I am trying to read an address from a memory location and then write into that memory location. i.e. unsigned long * mem_pointer = 0x93700020; //Valid memory location on my hardware unsigned long mem_value = *mem_pointer; //Retrieve the value (another memory location) from //the pointer The question is - How do i


Turning off memory chip to save power

Started by amerdsp in comp.arch.embedded12 years ago 4 replies

Greetings, What is a good way to control the power to a memory module. One of the memory modules (4MB FIFO) that I intend to use consumes...

Greetings, What is a good way to control the power to a memory module. One of the memory modules (4MB FIFO) that I intend to use consumes 14mA in standby mode, which is one order of magnitude of what I want. Is there a way to turn off power to components and use something in the order of uA instead of mA when not in use? Thanks, A


z80 memory io selection

Started by Frank Eggink in comp.arch.embedded11 years ago 12 replies

Hello, is it possible to use io on a z80 to select different memory chips. Something like bankswitching, using an out command to select a...

Hello, is it possible to use io on a z80 to select different memory chips. Something like bankswitching, using an out command to select a memory chip? Greetings Frank


How to read/write external memory with MSP430F1121

Started by DenCop in comp.arch.embedded15 years ago 6 replies

Hi hello, Maybe it's a stupid question, but how can I read/write external memory with a msp430. I have to store something like 15kB (not...

Hi hello, Maybe it's a stupid question, but how can I read/write external memory with a msp430. I have to store something like 15kB (not much). I thought about FIFO memory, because I think that will be the easiest way. I hope you can help me, DenCop PS sorry for my bad English


can't read load memory contents

Started by dartanian in comp.arch.embedded12 years ago

Hello there, one of new members around here. I've got a problem while i try to retrieve/pass over some values to memory. I use EDK 9.1 and a...

Hello there, one of new members around here. I've got a problem while i try to retrieve/pass over some values to memory. I use EDK 9.1 and a system of microblaze, opb bus and opb bram memory. I try to retrieve some values from memory through a vhdl testbench, which is port mapped in the PORT B of Bram (by making Bram's PORT B external) and then write back these contents in other blocks - a...


Top 10 Technical requirements for In-Memory Reporting

Started by JTP PR in comp.arch.embedded9 years ago

With Gartner's Business Intelligence group listing In-Memory analytics at the top of their recommended Business Intelligence requirements...

With Gartner's Business Intelligence group listing In-Memory analytics at the top of their recommended Business Intelligence requirements for enterprise; No wonder In-memory has become a trending topic in BI and a new addition to executive shopping lists. We thought we=92d share with you our top 10 technical requirements, you should be asking from an in-memory analytics vendor: [10] Be o...


Debugging using memory prints

Started by nived in comp.arch.embedded9 years ago 10 replies

Hi, I am faced with a problem of not being able to effectively debug what i am doing. Is it possible to save debug information at locations...

Hi, I am faced with a problem of not being able to effectively debug what i am doing. Is it possible to save debug information at locations in memory/flash and then examine them later ? Instead of say printing to the console, printing to locations in memory. Thanks - Nived --------------------------------------- Posted through http://www.EmbeddedRelated.com


flash memory(external)

Started by risha in comp.arch.embedded14 years ago 14 replies

need to know how to write data into external flash memory(offchip).using MCU MC9S12A128B and the external flash memory chip is M29F040B.Is there...

need to know how to write data into external flash memory(offchip).using MCU MC9S12A128B and the external flash memory chip is M29F040B.Is there any special code to be sent to the external flash memory.Using a cpld chip number being CY37128P84 125 JC which is used for the selecting the external flash chip.Also using metrowerks code warrior and BDM Multilink. Thanks for any help, Ranjita...


Architecture question

Started by Tim Frink in comp.arch.embedded12 years ago

Hi, I've 3 questions about my Infineon TriCore microcontroller which is described by Infineon as "32-bit microcontroller-DSP...

Hi, I've 3 questions about my Infineon TriCore microcontroller which is described by Infineon as "32-bit microcontroller-DSP architecture optimized for real-time embedded systems". According to the manual, the DSP has the following memories: · Data Memory Unit (DMU) with ­ 64 Kbyte of Data Memory (SRAM) ­ 16 Kbyte of Stand-by Data Memory (SBRAM) · Program Memory Unit (PMU) ...


Question about memory mapping in ARM processor based SoC

Started by Bhavik in comp.arch.embedded12 years ago 8 replies

Hello, I am working on embedded application development for ARM926EJ processor based SoC. As per my product specification, there are 2 SDRAM...

Hello, I am working on embedded application development for ARM926EJ processor based SoC. As per my product specification, there are 2 SDRAM memory banks which can address 128 MB SDRAM each. So the there could be overall 256MB SDRAM in the system. The board that I have has 128 MB of SDRAM as per the specification. So I suppose there is only one memory bank used with 128 MB memory. I ...


Memory choices

Started by Joe G (Home) in comp.arch.embedded10 years ago

Hi All, I am developing a ARM9 system, The ARM9 has an external memory controller on board. I am facing some choices in memory as the...

Hi All, I am developing a ARM9 system, The ARM9 has an external memory controller on board. I am facing some choices in memory as the memory controller can use SDR SRAM and DDR SRAM , as well as other features. Can comment on the following choices (price and availability, popularity) SDRAM (512Mbyte total) SDR or DDR SDRAM ? Data width x8 x16 x32? NAND Flash (128Mbyte...


Dynamic Memory Usage using Linker Script Programming

Started by karthikbg in comp.arch.embedded12 years ago 1 reply

Hi, I got some special tricks for the Linker Scripts for a non-contiguous memory map in which i can distribute code or data among more than one...

Hi, I got some special tricks for the Linker Scripts for a non-contiguous memory map in which i can distribute code or data among more than one memory area. MEMORY { PR_MEM1: origin = 0a000h, length = 0500h; PR_MEM2: origin = 0d000h, length = 0300h; } SECTIONS { .text_1: { test1.obj(.text), test2.obj(.text), test3.obj(.text) } > PR_MEM1 .text_2:


HC11 EVS board specific problems

Started by Anonymous in comp.arch.embedded12 years ago

We have been successfully using the EVS setup for many years. We have just seen a problem and are not entirely sure how to go about solving it....

We have been successfully using the EVS setup for many years. We have just seen a problem and are not entirely sure how to go about solving it. Whenever attempting to modify memory locations, the emulator interface spits out the error "Corrupt memory at address xxxx" (we are using the E9 and the entire $D000 block of memory is corrupt, thus inhibiting us from loading or running programs.) ...


STL containers and managing memory allocation in embedded systems

Started by Alex Vinokur in comp.arch.embedded13 years ago 26 replies

The memory allocation issue in embedded systems is usually critical.. How can one manage that? 1. Via 'new' char* p = new (nothrow) char...

The memory allocation issue in embedded systems is usually critical.. How can one manage that? 1. Via 'new' char* p = new (nothrow) char [SOME_SIZE]; if (p == 0) { // He we know that it is impossible to allocate the requested memory // We can do something relevant. } 2. But how to manage memory allocation in containers for embedded systems? For instance, vector v; F


DMA transfer size limited on MPC8272

Started by Bill in comp.arch.embedded12 years ago

I am DMA'ing from 60x memory to PCI memory and from PCI memory to 60x memory in a Linux device driver using the MPC8272 processor. The...

I am DMA'ing from 60x memory to PCI memory and from PCI memory to 60x memory in a Linux device driver using the MPC8272 processor. The DMA completes but the logic analyzer shows that the DMA is broken up into a series of 32 byte (8 dword) transfers, no matter what the byte count is in the segment descriptor. Shouldn't I be able to do the transfer in a single DMA transfer? If so, how? Is t...


The cost of malloc()

Started by Vladimir Vassilevsky in comp.arch.embedded12 years ago 3 replies

When allocating a chunk of memory with malloc(), there is always some memory overhead associated with the heap control structures. Also, the...

When allocating a chunk of memory with malloc(), there is always some memory overhead associated with the heap control structures. Also, the minimum memory allocation unit is typically larger then one byte. Because of that, sometimes it could be more efficient to allocate a static data of the maximum size rather then a dynamic data of the required size. I understand that those thin...


SD Memory Card - Microcontroller Interface

Started by Anonymous in comp.arch.embedded15 years ago 5 replies

Hello, I don't have a particular project in mind, but it seems like having 512+MB of memory at my disposal for microcontroller projects would...

Hello, I don't have a particular project in mind, but it seems like having 512+MB of memory at my disposal for microcontroller projects would be quite amazing. From a few of the posts I've read, and the limited specs I could find, it seems like Secure Digital (SD) memory cards allow for an SPI interface (serial) and run anywhere from 0-25Mhz. (I've interfaced to CompactFlash cards and Car...


Required memory estimation.

Started by JY Kim in comp.arch.embedded12 years ago 2 replies

I need to pre-estimate required memory of our project I have experience in device driver programming of PocketPC but I have never done things...

I need to pre-estimate required memory of our project I have experience in device driver programming of PocketPC but I have never done things like this before I am using ST STR7 32bit arm7 mcu without OS, but our final goal is using OS my company has developed. I think currently only method by which I can assume required memory is just counting byte. Then what I add to estimate required mem...