Which controller to use?
in [Embedded]
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From: FJG on 4 May 2010 16:01 As a coder I've usually had custom hardware to work with and the choice of architecture etc has been cost-driven and set in stone long before I start trying to debug the board... but I digress. I have a potential project coming up, where I may have some influence on the hardware. The spec is of necessity still slightly woolly, so my apologies for that in advance. The basics are input - RFID tags, info probably read over RS-232 output - solenoids / relays to turn a motor on I/O - USB memory stick to upload new settings, download reports control panel - three buttons and possibly a cheap LCD display optional - WiFi interface weatherproofed - will operate outdoors, off 12V DC ROM / RAM / CPU requirements are going to be modest by today's standards. We're talking about, say, 200 RFID tags to recognise, each of which has an individual setting for the amount of time to turn the relay / solenoid on for. So any suggestions for a single board microcontroller that'd provide the above at reasonable cost, with the minimum of hassle, with a (preferably free) C toolchain? Personally I think the idea of a USB port on an outdoor piece of equipment is a bit nuts, so any suggested alternatives? Bluetooth?
From: hamilton on 4 May 2010 16:17 On 5/4/2010 2:01 PM, FJG wrote: > As a coder I've usually had custom hardware to work with and > the choice of architecture etc has been cost-driven and set > in stone long before I start trying to debug the board... > but I digress. > > I have a potential project coming up, where I may have > some influence on the hardware. The spec is of necessity > still slightly woolly, so my apologies for that in advance. > > The basics are > input - RFID tags, info probably read over RS-232 > output - solenoids / relays to turn a motor on > I/O - USB memory stick to upload new settings, download reports > control panel - three buttons and possibly a cheap LCD display > optional - WiFi interface > weatherproofed - will operate outdoors, off 12V DC > > ROM / RAM / CPU requirements are going to be modest by today's > standards. We're talking about, say, 200 RFID tags to recognise, > each of which has an individual setting for the amount of time > to turn the relay / solenoid on for. > > So any suggestions for a single board microcontroller that'd > provide the above at reasonable cost, with the minimum of hassle, > with a (preferably free) C toolchain? > > Personally I think the idea of a USB port on an outdoor piece > of equipment is a bit nuts, so any suggested alternatives? > Bluetooth? USB in any embedded device is a bit nuts, but I digress. You are not going to find USB master on a poor 8/16-bit micro. Only 32 bit devices have USB master. So, if you think your doing to get it cheap........ Everything else is doable with any micro-controller ( or two ). Google for WinAVR, free tool chain and Atmel AVR family is very robust. I have done two products with these tools. hamilton
From: Rob Gaddi on 4 May 2010 16:40 On 5/4/2010 1:17 PM, hamilton wrote: > [snip] > > You are not going to find USB master on a poor 8/16-bit micro. > > Only 32 bit devices have USB master. > > So, if you think your doing to get it cheap........ > > [snip] You mean like a Cortex-M3 for south of $2, or a Cortex-M0 for south of $1? -- Rob Gaddi, Highland Technology Email address is currently out of order
From: linnix on 4 May 2010 17:01 On May 4, 1:40 pm, Rob Gaddi <rga...(a)technologyhighland.com> wrote: > On 5/4/2010 1:17 PM, hamilton wrote: > > > [snip] > >> You are not going to find USB master on a poor 8/16-bit micro. > > > Only 32 bit devices have USB master. > > > So, if you think your doing to get it cheap........ > > > [snip] > > You mean like a Cortex-M3 for south of $2, or a Cortex-M0 for south of $1? Not with usb host. With host functions, pins and costs go up, not that they are correlated. > > -- > Rob Gaddi, Highland Technology > Email address is currently out of order
From: Fevric J. Glandules on 4 May 2010 17:22
hamilton wrote: <snip> > Only 32 bit devices have USB master. > > So, if you think your doing to get it cheap........ I'm sure 32 bits is fine. > Everything else is doable with any micro-controller ( or two ). Sure. What I'm looking for is a module / single-board computer / whatever you want to call it that will provide as much out of the box as possible. Even some sort of "hobbyist" kit would be fine if it provided 12V relays for controlling motors, debounced buttons, a small LCD output, etc. E.g. http://rabbit.com/ is under consideration. |