• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

FPGA Power vs uC

Status
Not open for further replies.

DirtyLude

Well-Known Member
Atmel whats? Your question is way too vague.

A google search couldn't find anything on LC2214. Did you mean LPC2214? It's not an FPGA.
 
Last edited:

CoTang

Member
Haha, sorry thats an Arm I believe....LPC2214.

Damn. Let me try again. If there is 10 atmel 8 bit (commonly used uc) what can I use to replace those 10 that can do the same thing but has more power.
 

Sceadwian

Banned
FPGA's and UC's are totally different worlds. And if Dirty's guess is correct the LPC2214 isn't an FPGA it's an ARM processor. Your question still doesn't make much sense, even the slowest AVR is not going to have trouble logging data once per second. If you run out of memory use an external flash/eeprom or sram module.
 

DirtyLude

Well-Known Member
There are definitely things that FPGA's are very fast at, but they usually have pretty specific uses. They generally aren't used as direct replacements for uC's in final development. There are very fast uC's like ARM9's and ARM Cortex if you just want speed.

Someone posted this link a while ago, and it's pretty nice for beginner FPGA.
fpga4fun.com - Welcome
 

CoTang

Member
I apologize if my question doesn't make much sense. I'm just started looking into other possible devices to reduce the uC that is used. I'll try to explain the current situation.

I have 10 sensors that is connected to 10 A/D and each one is tied to an atmel 8bit uC that samples at say 1/s. Each individual sample is stored in their own external memory. Now what I want to know is that is there a single devices (whether it be another uC or FPGA or ARM...) that will replace the atmels 8bit and still handle more if needed say maybe up to 50 sensors and 50 a/d etc...oh yeah they all need to be triggered and sampled at the same time.
 

Sceadwian

Banned
You're sampling 10 sensors from 10 different chips? Haven't you ever heard of analog multiplexers? You can get AVR's with at least 11 multiplexed channels for it's single ADC and the ADC is 10 bits.
 

CoTang

Member
There are definitely things that FPGA's are very fast at, but they usually have pretty specific uses. They generally aren't used as direct replacements for uC's in final development. There are very fast uC's like ARM9's and ARM Cortex if you just want speed.

Someone posted this link a while ago, and it's pretty nice for beginner FPGA.
fpga4fun.com - Welcome
hmmm that link explains a lot!

Since the current situation is all digital logic except for the sensors to a/d (which is triggered and converted to digital) an FPGA looks like an idea candidate due to the parallel feature although the uC has some too, the FPGA has more I/O for that....

Any site on ARMs? I like to read up on those to get a better idea....
 
Last edited:

Sceadwian

Banned
You're talking about 1 reading per second... FPGA's are so overkill for that it's not even funny, because you'd STILL have to add on ADC circuitry. Using a SINGLE AVR with analog multiplexers would work, if you need more than the number of channels the AVR itself can provide use external analog multiplexers. Use an 8 channel multiplexer on each of the 8 pins of a multiplexed AVR and you'd have the possibility of 256 channels, using a single AVR.
 
Last edited:

CoTang

Member
Well first off, I didn't build the original device. I'm researching ways to improve it better. When I heard about that I also said "what the hell?".

Anyways, thanks for the input.
 

DirtyLude

Well-Known Member
Any site on ARMs? I like to read up on those to get a better idea....
I don't know of any websites that have a basic overview of ARM chips. ARM is the processor core and the different manufacturers, like Atmel, NXP, ST... add all the peripherals. Changing from one ARM7 from one manufacturer to another means you'll have to rewrite the code that access the peripherals, but they are close enough that it's not that difficult.

Essentially there is no difference functionally between and ARM7, or ARM9, and an AVR or PIC. They are just microcontrollers, but they are 32 bit with an optional 16bit mode. They have control registers for peripherals like GPIO's and ADC's and interface peripherals like I2C and SPI and UART... just like the smaller 8 bits. Some have built in EEPROM/RAM and some require you use external ROM/RAM.

I would have to agree though, any single 8bit controller can handle the task that you have. 1 second, or even half and second, or even a 10th of a second they can sample and store hundreds of log samples. They'd be likely more restricted by the ADC speed and the EEPROM access speed, if you are actually using EEPROM and not something faster.
 
Status
Not open for further replies.

EE World Online Articles

Loading
Top