Tagged Questions

2
votes
3answers
232 views

Interfacing with RAM from a PC, e.g. SDRAM / DDR, to a microcontroller

I'm looking into interfacing standard PC form-factor SDRAM or DDR sticks to a microcontroller, but I can't find any definitive details on how they work in terms of how the bus works. I guess it's ...
1
vote
1answer
102 views

SDRAM on opposite side of board with respect to uC

Just a quick question. Is it advised against to place a high speed memory device on the opposite side of the PCB with respect to the microcontroller? And if it is ill advised, how is it possible to ...
3
votes
1answer
106 views

Memory interface for video output

I am designing a system where a DSP (like the TMS320VC5501) processes some video data and outputs it to a PSP screen (the ones sold on sparkfun). The issue I'm having here is designing the video ...
4
votes
4answers
280 views

SDRAM advantages

As of RAM technologies (the basic ones) is concerned, I consider the initial classification (based on the storage) as SRAM: The basic entity for storage (each cell) is the flip-flop (comprised of ...
4
votes
3answers
481 views

How does random memory access of RAM work?

HDD works in a partly sequential manner. However, RAM is known for random memory access, allowing equal speed of memory access for every location at every time. So, what makes RAM so special? How ...
6
votes
1answer
286 views

Freezing DRAM for forensics (coldboot)

I've known about the coldboot trick for a while, but have never really considered the physics behind it. I've read the paper, but it doesn't really cover why it works. How does physically cooling a ...
8
votes
3answers
617 views

SDRAM Prototype vs Production Woes

I have a design using an LPC1788 together with a SDRAM module from ISSI (IS42S32800D). This is a 32bit interface. I have routed this design out and had a prototype made with a PCB manufacturer that ...
3
votes
1answer
313 views

What are these pull ups for on this SDRAM?

Apologies for all these questions about SDRAM, but I want to get this next board run right. I have an LPC1788 processor with an external memory controller I am interfacing with SDRAM. There is no ...
2
votes
1answer
250 views

Interface Mobile SDRAM (1.8V) with 3.3V SDRAM controller

I am looking for a 256Mbit SDRAM module in BGA format, to buy in units of 1000. However the cost for these modules are extremely high for packages using a 32bit bus in standard 3.3V voltages, however ...
2
votes
3answers
987 views

SDRAM issue - LPC1788

I have been using an NXP LPC1788 dev board which I have developed my application on (.NET Microframework Cortex-M3 Port). Everything was well and good on this board, I had no issues with RAM or ...
2
votes
3answers
703 views

I know why DRAM is slower to write than to read, but why is the L1 & L2 cache RAM slower to write?

DRAM is slower to write than read because it takes time to either charge or discharge a DRAM memory cell. But what about the SRAM in my processor's L1 and L2 caches? It's slower to write as well but ...