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LAN_403

Shrad

Fri Feb 07 2014, 08:41PM

Registered Member #3215 Joined: Sun Sept 19 2010, 08:42PM
Location:
Posts: 780

may I kindly suggest you to use such a screen?

you can draw things and write text via some serial commands like line(12,30,18,52) to draw lines and other primitives, as well as some commands like putScreen(x,y,data) to output an array of pixels at a place on the screen like you would do for an oscilloscope (frame buffering)

Andy

Fri Feb 07 2014, 10:06PM

Registered Member #4266 Joined: Fri Dec 16 2011, 03:15AM
Location:
Posts: 874

Thanks for the link Shrad, found this, I think its what you link to

Have you got a link to some C examples of how to use the LCD you linked to?

Cheers

Shrad

Sat Feb 08 2014, 07:11AM

Registered Member #3215 Joined: Sun Sept 19 2010, 08:42PM
Location:
Posts: 780

this is horribly expensive

just get a chinese one, they are as good

all you have to do is send a text command via the serial port of the screen

the screen controller will have a datasheet which lists the configuration of the serial port as well as how to send commands

there are no examples in a particular language, you just send the screen a set of commands via the serial interface

the best thing you could do is buy a cheap chinese one and test it with a serial link and a terminal on your computer

these woudlwork too:

but I don't know how to use them and you'll have to search for info, I just know this is quite easy to implement

Proud Mary

Sat Feb 08 2014, 07:28AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

I'm sure you've got plenty of good quality test equipment to analyse and de-bug this thing during the inevitable prototype stages you will have to go through to produce a reliable and accurate instrument, or you wouldn't be doing it.

For myself, I only make and use what I'll call secondary measuring instruments, whose accuracy is ultimately derived from some other instrument of known quality.

For example, I'm happy to build an RF impedance bridge, or a gauss meter, or a rate meter, but I wouldn't think of building a DMM or an oscilloscope because without economies of scale I would end up paying far more than I would have done if I'd just gone out and bought a new instrument with a calibration and safety certificates stapled onto the guarantee.

Trying to copy - needlessly - mass-manufacturing techniques like SMD wave and robotic soldering is a recipe for humiliating disaster. SMD technology is not designed to be assembled by humans.

Why not save yourself a lot of grief and go out and spend the same money on a decent bench multimeter with USB, and a cheaper DMM for measurements where there is a risk of HV damage - i.e. most of the projects in this forum.

Anyway, I don't suppose for a moment you'll take my advice, but someone owes it to you to tell you the truth, so good luck with it all!

Andy

Sat Feb 08 2014, 10:47AM

Registered Member #4266 Joined: Fri Dec 16 2011, 03:15AM
Location:
Posts: 874

Shrad

Can't beat that price

pdf has the info I'm after

ProudMary
I'm not after 100% accuracy in the measurement, just ball park figures, maybe 2-5% off, the device will all so be a laptop, web browser, email, and one or two other things. There might be something like this that is cheaper to buy, but the skills learn't will let me build something that hasn't been already built.
I'm listen, just have selective hearing

Erlend^SE

Sat Feb 08 2014, 05:06PM

Registered Member #1565 Joined: Wed Jun 25 2008, 09:08PM
Location: Norway
Posts: 159

Andy:
First, you should use a ARM processor so you can load android or linux onto it.
Add 1 MB ormore of RAM for a start.

The display: Paralell scanned interface, CPU spesific

The scope: fast A/D converter loaded into the CPU by DMA, trigger by software or hardware

Debugging: route out some UART pins for console (when testing)

Battery: Li-Ion system, with protection module and proper charger IC

Board: 4 layers or more, with ground & vcc planes.

Not that trivial to get it to a really usefull state.

You could as well look at android's docking protocol, only need the scrope A-D and data-transfer stuff that way.

Shrad

Sat Feb 08 2014, 06:59PM

Registered Member #3215 Joined: Sun Sept 19 2010, 08:42PM
Location:
Posts: 780

if a raspberry pi fails loading google page (fails as takes ten minutes to load) then I can't see you doing better without having a whole team

Andy wrote ...

Shrad

Can't beat that price

Andy

Sat Feb 08 2014, 07:54PM

Registered Member #4266 Joined: Fri Dec 16 2011, 03:15AM
Location:
Posts: 874

Erlend^SE
I will be following most of the list thanks, apart from the core, I'll be using 20 Pics, with 10 Pic for the instructions, it will have software chip emulator, of the ARM processor, x86 will be difficult to setup A20 lines/RAM/GDT and all that crap. Didn't think about debugging,Theres some software code for on Microchip direct that has DMA stuff with UART to hyperteminal, will go back and download
With 4 layers, how do you join up the middle layers? or does the chop shop do it.

Shrad
I will be using other peoples code for the web browser etc, I just need to code the emulator, which I've done before and it worked. The hard part will be getting 10 cores to parallel good, but at 800Mhz over all core.

Shrad

Sat Feb 08 2014, 10:03PM

Registered Member #3215 Joined: Sun Sept 19 2010, 08:42PM
Location:
Posts: 780

the raspberry pi is 700Mhz

maybe you could try the new development board from Intel which is arduino-compatible (I think it is the Galileo)

Andy

Sat Feb 08 2014, 11:19PM

Registered Member #4266 Joined: Fri Dec 16 2011, 03:15AM
Location:
Posts: 874

Yeah I guess I'm going to have to think about this some more, found

and

, its abit faster and has more pins,per space, I do abit more reading and see if I can get these to work.
For the CPU core, I might use a raspberry pi.

I'm thinking about getting this

, to put the chip on, are SMD that bad?

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