Matrix user forums

Alleluia! Discovered that the scope’s failed chip has 2 clock outputs, with one unused. So have swapped to the other one and regained the display as in these photos. It shows how bad the old one is as can only read a few things in the corners. SDC18546.JPG SDC18547.JPG I think I have also shorted ou...

How do interrupts work at the nanosecond level in PICs and Flowcode? Say I have a 8 bit all port interrupt. When any of the 8 bits changes state it triggers the interrupt “instantly”. But in practice I assume that it works at processor clock speed rather than instantly so needs say 1 to 4 clocks to ...

HDM3224L-G Hantronics.pdf There is good news and bad news. I paused the development as Hantronic, despite publishing lots of data, could not tell me if the bias voltage for the obsolete display I bought was +30V or -30V and using the wrong one may destroy it. Their current models are either not sui...

Lots of good ideas thank you very much. The next step is for me to actually try some hardware out to see it displays anything. That is going to take some weeks as some of the bits like LCD and ribbon connectors I ordered come from China. When I have something running I’ll probably be back asking mor...

Scope clock pulses.pdf Here is a doc I wrote showing some scope traces measured off the faulty scope with a good Picoscope. You can clearly see the double pulses with a variable gap to next pair. I have assumed no significant gap after each frame as yet to measure that. The refresh rate would be le...

Hope this works but have included some of your text in italics to make it easier to show what I am replying to. I was a bit unsure where the stretch clocks went out - so I've put them after odd pixels - this might need tweaking... . Think it's correct. Should be, half a nibble, 1 stretch bit, half a...

Martin, does not answer your last post but here is a fcf that: Reads the 2 nibbles on an interrupt. When that is complete parses 2 nibbles into 8 variables. (But may be able to do the first nibble in the interrupt to save time). In Main output that as 12 serial bits plus 12 serial clocks (to add the...

For speed you could possibly either use a switch (or a jump table, though not easy in Flowcode) So in pseudo code: b = Read 4bits Switch on b 0: Writepixel(0)x4 Another approach might be to read the entire frame to memory - then process it ( and write to output) in the delay between frames (assumin...

So to get 16 instructions into 0.25us I'd need a PIC 16 at 70MIPS. As the real instructions for above interrupt macro are probably 50 or more I'd really need a PIC32 which go up to 250MHz. Although it's getting a bit ridiculous to use a 64 or more pin PIC 32 device when I only use about 6 I/O pins i...

http://www.microchip.com/ParamChartSear ... ranchID=20 only lists up to 70 MIPS although it does say DMIPS too. Is that double MIPS? But have found that page lacking as some in production PICS don’t appear there at all.

Thanks Martin. Realised I have a speed problem in that the minimum period of the data clock pulses is 250ns. A 4 bit nibble needs to be read in that time and output as 4 individual pulses on a one bit o/p as well as a clock of 4 times the input data clock. This is really pushing the speed of a PIC a...

Mea cupla. There was a tick box say something like "Are you sure you want to make changes ?" that I had missed.

Not tried all those things yet but re downloaded it from the other site and using a different browser and all copies have a slightly larger 1,169,186,816 bits and not the size you mentioned. Why?

Medelec, I left it running to install so don't think that is the problem.

Had to rename file as won't accept .log attchements

Thanks. Sorry I need more explanation. Do I need to run the installation again after entering this cmd line? Does Program Files (x86)\ need to go after each C:\ as that is where the FC7 was trying to install? Tried it on the cmd line and gave error message with or without that extra bit. There was n...

Many thanks kersing. There are lots of chips that do video conversion, e.g. from RGB to HDMI for TVs, PCs etc. but can’t find one that does what I need as the scope LCD uses a rather unique graphics controller made from 6 chips that can no longer be bought (rather than the one normally used) and the...

Tried twice to install v7 to try it out and it gets to the "end" of install and says "setup was interrupted ... run setup again." How to fix? I have Windows 7 64 bit.

To distil the random musings into actual Flowcode questions can I ask? 1. Do you support PICs with more than 15kbyte of RAM as need that to save a full video page array? Such as dsPIC33FJ256GP710A. No 8 bit PIC has enough RAM. 2. Do you support adding an external 16kbit RAM to an 8 bit PIC? Suspect ...

Sorry about these random musing, I am learning a lot about video protocols. One flaw in having no controller on the LCD is that the PIC not only has to accurately synch with the scope to read the data, but also has to issue accurate timings to the LCD and I can see that may be difficult to do, with ...

Think though if using the Hantronics one that it might be necessary to use a PIC to fill in the missing 80 columns in the scope signal so can't manage without a frame store in PIC to do this. I have measured the refresh rate as 36Hz. Fundementally I now think what I need to buy is a lcd without a co...

Looking at the common ILI9341 controller chip for 320x 240 displays (has 1278 pads to drive all those rows and columns etc.!) it has a SPI data speed of 10Mb/s. To enter a full screen into its RAM takes 240 x 320 x 18/10,000,000 = 0.14 secs as each pixel needs an 18 bit colour stated, even though I ...

I have an expensive oscilloscope with a fading and obsolete 240x 240 pixel LCD graphical display. As 320 x 240 displays are cheaply available for Arduino and Pi use I am thinking I can get one of those and use a PIC as a protocol converter to read the existing display data and translate it to someth...

Any plans to add any of the 16(L)F178x family especially the middle of the range like 16F1786? These have a 12bit ADC instead of the more usual 10 bit so I wanted to use one.

Or is there a PIC with 12bit ADC with 20 – 28 pins that you do cover?

Aside from the hex file what data/file does the loading software, be it PICkit’s version or Flowcode’s, pick up to create the entire load? Something to do with clock speed and config words?? I think it is this side of things that is going wrong. I am using Windows 7 on the dual PC and Visa on the ot...