Mecrisp on the TI Stellaris Launchpad

I'm not 100% certain of this, but I believe the rPi runs input power through a Polyfuse which does have some noticeable resistance and so voltage droop. I've cross-posted this to the rPi group to see if anyone will confirm it.

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Rick
Reply to
rickman
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Do you not understand what I was doing? I was working on compiling an executable to see if it worked. Before I went to the bother of (if I was ever going to) copying the exe to one of the bin directories, I wanted to test it. I likely won't move it to a bin directory because it is likely not more than a one time use thing.

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Rick
Reply to
rickman

I'm appending this OT post because I don't often look at my own posts, but did this one. I'm using Thunderbird and it seems to do odd things with line breaking.

It is common that I reply to ("Followup" in T-bird parlance) a post only to find quoted lines extending off the page. Ok, so T-bird doesn't always figure out that it needs to wrap lines for display.

But looking at my own post, I see the lines wrapping, but at the edge of the screen, not at the 72 column point where line breaks should be inserted when sending a message. Changing the size of the window confirms this.

Then to make it even more confusing, in this reply it would appear that line breaks are inserted in the quoted text! WTF????!!!! Anyone understand how T-bird handles the line breaks, word wrap features? Do you see my posts with line breaks at 72 columns? I have that turned on... at least I thought I did. I can't find the setting now.

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Rick
Reply to
rickman

I never work in my home directory, always in PROJECT/ or $HOME/euler or sometimes in /tmp. But I do make programs there that I want to run, all the time, up to a hundred times a day, easily. Need a test version of lina with a cramped 2M dictionary space? " lina64 -i linaG forth.lab \ install copy in current dir linaG -g -7998 lina \ "grow by" minus 7998 Megabyte. rm linaG "

That is indispensable for all kind of utilities.

Groetjes Albert

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Albert van der Horst, UTRECHT,THE NETHERLANDS 
Economic growth -- being exponential -- ultimately falters. 
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Reply to
Albert van der Horst

This has been rewrapped by Pan because it needed to add "> " at the beginning of each line, but as received, your appended text was wrapped at between 71 and 74 characters. I think it wraps whenever the next word would make the line longer that 74 chars, which is a bit odd seeing that you set the limit at 72. The last word at the end of each line in the para were:

that Anyone you at now.

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martin@   | Martin Gregorie 
gregorie. | Essex, UK 
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Reply to
Martin Gregorie

When in doubt check the spec... USB2.0 ports are 5v +/- 5% so 4.75V to

5.25V between the pins on the connector.

4.95 is almost perfectly in the middle.

Reply to
mm0fmf

Thanks. The 72 columns was just my recollection. I can't find the setting now.

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Rick
Reply to
rickman

I never said that measurement was out of spec. I was commenting on the facts that there is a quarter volt lost across the rPi and that the launchpad seems to reset when I type on the USB keyboard. Maybe it's not voltage related, but the quarter volt drop is unexpected and there are plenty of cases where even an older mouse, like the one I have, can't be powered through the rPi.

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Rick
Reply to
rickman

Yes, really.

I don't think that argument works.

There have been platforms where a very large fraction of users never wrote a program of their own. The biggest of those has to be Microsoft Windows, closely followed by MacOS.

But Unix never was anywhere near the top of that category. I'm not aware of any system that encouraged users to write their own programs more strongly than Unix did: the whole "toolkit" paradigm almost forced _users_ to become programmers, at least at the shell script level. And how many other systems did come with a bona-fide HLL compiler right there in the box?

And that was baskk-ackward. If only because it's a whole lot easier to and type the "./" prefix for the exceptional case of wanting something else than the normal instance of a command, than it would be to figure out where the "official" one might be, and type the full path to there every time you want to be sure you get that.

The distinction between "gforth" and "./gforth" is way easier to handle than the one between "/opt/swserver/Forth/GForth/V5/patch1/bin/gforth" and "gforth".

That workaround would be half-assed at best, because it relies on the obviously flawed assumption that user will never mis-type commands. But because they do, it's relatively easy for an attacker to pre-load their traps with lots of mis-typed versions of, 'ls', 'cd', etc.

One other rather important aspect is that the way Unix does it actually leaves you a _choice_ how you want this handled: _you_ define your $PATH setting, so you can put '.' in there exactly where you want or need it, or not at all. On Microsoft platforms, you have no control over it: the system forces an implied '.' to the front of your PATH, whether you want it or not.

Reply to
Hans-Bernhard Bröker

I don't wish to insult anyone. But I will say that I have tried to learn linux several times and found poor support from the linux community. Mostly I think there is an attitude that "we" (the linux community) got it *right*, when there are many, many more PC users, even professional programmers, than there are working under Linux.

Ok, everyone is entitled to their opinion. But the problem arises when it is not understood that this is an opinion, not a universal truth. There are good and bad things about both linux and windows. I would like to learn about linux now, so I won't ask "why" anymore. I'll just accept the things that are goofy about it just as I have done with windows for many years.

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Rick
Reply to
rickman

Linux has its roots in Unix which goes back to the 1970's, long before the existence of PC's, so it tends to use old-school approaches:

formatting link

Reply to
Paul Rubin

Now I am a bit stuck trying to get a serial port terminal emulation running. It would appear that miniterm is the right program to use, but while dealing with the slowness of the rPi when web browsing I have yet to find it exactly. I thought I had found it at a site called Py Serial. But I think what I downloaded with some sort of python wrapper for miniterm. I'm not sure really.

Even once I get a terminal emulator running, I'm not sure how to find the ID of the device I'll be talking to with it. It is a TI launchpad with a USB emulated UART. These things are like falling off a rock in the PC world... mainly because I've come up the learning curve and know it. Will miniterm have the smarts to find the one serial port on the machine or do I have to figure out the ID of this USB serial port and tell it?

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Rick
Reply to
rickman

Do "ls /dev/tty*" and it should give you a list of possible devices where the port is.

Do you use irc? You can probably get quicker help on the #raspberrypi Freenode channel.

Reply to
Paul Rubin

I'm going to get the better computer, but it costs $35. The rPi 2... This thing is not much of a desktop. I have a 10 year old machine that runs XP and does rings around the rPi. But then it has it's own table, burns enough power to warm a cat very nicely while the rPi serves as a night light and sits on top of my monitor... lol

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Rick
Reply to
rickman

The Rpi is an embedded linux board that I hope is not being sold as a desktop. The Rpi2 has four cores each around 1.5x the speed of the Rpi1, and I don't know if the parallelism will really help with web browsing. I can understand not wanting to lug a full sized laptop around but there are some very nice, fast ultralights around these days. I want one of these:

formatting link

Ironically one of the easiest places to go look at one in person is the Microsoft store. But I'd buy the Linux version above.

Reply to
Paul Rubin

That gives me a list of tty, tty0 through tty63, ttyAMA0 and ttyprintk. The list is the same if the device is plugged in or not. Of course, I don't know for sure what the board should do, but my understanding is one port is for use as a debugger and this port is for use as a UART interface to the target MCU. I had found a web page where they were developing on this target under Linux. I'll go back to that to look for info. But I think it was more debugger oriented.

Trouble is most of these pages are from experienced users and they have long ago forgotten all the small stumbling blocks to getting started.

I'm not familiar with irc. I think I tried it once a long time ago and didn't get much traction with it. I'm expecting there should be knowledgeable people in the rPi group.

One of my problems is there really isn't room for the pi, the laptop and all the other misc stuff on my work table at the moment. Maybe I need to just work remotely from the laptop. That would solve my lack of a USB hub as well. I have to unplug the mouse to plug in the launchpad.

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Rick
Reply to
rickman

My problem isn't the size of the laptop exactly. It is the smallness of the space available, lol. I can't use such small machines really. In fact one of my complaints of this 17" laptop is they didn't use all the space available for the keyboard so there is no space between the key sections. It is impossible to feel for any keys like the arrows or the Home, End, PgUp, PgDn keys. You have to look every time you reach for one. Then the rPi is tiny, but the 19" monitor is not and the compact Dell keyboard is wider than the 17" laptop, along with all the tools, drawers, lamps, outlet strips and misc junk on the relatively small table top. If I put the laptop where the keyboard is I have to lay the keyboard behind it... I could bring another table in just for the laptop. Or I could admit I am never going to fire up the XP computer again and use that tray.

But for the short term, I'm just looking for a way to talk to the launchpad from the rPi.

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Rick
Reply to
rickman

Usenet probably predates the rpi by too much. I'd suggest: download an irc client (xchat.org has a nice one), connect to irc.freenode.net and join the #raspberrypi channel. There are also some web based clients but I've always found them annoying to use.

Reply to
Paul Rubin

On Fri, 17 Apr 2015 20:20:30 -0400, rickman wrote: [ ... ]

What do you mean by USB emulated UART? When I plug one of my Sparkfun FTDI boards into a Pi, it shows up to lsusb as "0403:6001 Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC" and gets assigned to /dev/ttyUSB0. A different device, Arduino based, announces itself as "2341:0010 Arduino SA Mega 2560 (CDC ACM)" and gets assigned as /dev/ttyACM0. This is on a stock Raspbian distribution. The difference between the two is apparently that the FTDI emulates a UART, whereas the Arduino emulates a modem, and that's somehow recognized when they're establishing the USB connection. If the Launchpad is supporting serial/USB on its own, as the Arduino is doing, I'd suspect it's following one of these two regimes, but it's up to udev rules in the Raspbian configuration to know this, probably from the manufacturer and device codes. Hope this helps -- it's the limit of what I know.

Reply to
Mel Wilson

OTOH, even MS has decided that the Unix behavior is the correct one, and PowerShell, largely the replacement for the old command prompt, does *not* search the current directory for executables first.

Reply to
Robert Wessel

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