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turn LCD 180 degree


Marxon

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Hi evrybody,

i wonder if its possible to change thy display driver to use it "on the hat"

because the pins of my display are on the right side but it doesn't fit in my case.

i want to turn it 180 degree to have the pins on the left side. any ideas?          thx BpM

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I guess you're not talking about reversing the actual "pin order" ;) (too many non-data pins would show up in weird places)

If you mean writing "upside-down" to the display, I think the character LCD's recognize a set group of codes for the characters, so I'm not sure even a massive software hack would be able to send them upside-down.

(someone please correct that if it's wrong)

Take Care

George

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BpM,

Figured you might like to see this core thing I've been messing with

the past few days, but was on the way out earlier and didn't have a

picture.-

LCDTop.jpg

I've gotten into smushing things lately. ;D

I've hit similar deals as you, with the LCD connection, but with me, it was that the header layout didn't match either of the two types I've got (16pin 2x16's and 14pin 2x40's with 2 BL leads). I also wanted something I could carry around with no outside jacks or wires, other than the MIDI and power, so I moved the LCD header to the end of the PIC (after arranging the pins), and used a female socket, so I can press it directly onto the core. It's got holes to screw it on, but I'll do that later.

Coincidentally, when I was laying it out, I was forgetting that the LCD was going underneath it, so I ended up with the jack on the right and an upside-down deal, like you were asking about (but not a usable one). I ended up having to re-route all the LCD paths to go the right way, and move those two buttons. >:(

I guess at least I hadn't etched yet. :)

Here's one with the display pulled off.-

UnderLCD.jpg

I think that's about as "smushed" as it's going to get here, unless I can get a surface mount PIC. Seems like it all works alright, but I made my usual one or two stupid, careless mistakes, so I may change a few things and re-do it.

Take Care

George

PS- How fast would anyone here guess an 18F PIC/LCD would eat up a 9V battery?

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Hi Jidis!

Youre core looks very minimal, does it fit in a box of ciggarets?  ;D (bad english, i know;)

Yes it seems self etching is the best way for building it "wire-free"

I also have problems of wires which are to short, to long, broken or bad soldered.

dont ask me how many days i worked on my lcd cable  :-X

So i am going to etch my own pcbs for seq. Time shouldt be the same...  greatz bpm

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Jidis!

Now You got long plentiful Applauds from me!

Just if Midi had enough power to share (or LCDs low enough current consumption)... (Plug'n'go midimonitor :D)

Moebius

P.S.  BpM - It's not possible to actually "reverse" the characters programmably. Doing it by using 8 programmable characters inside HD44780 controllers is "Hackaday" stuff  ;D

Moebius

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@Moebius- Is that a verification that the character display chips are indeed only set to support a fixed group of characters? (just wondering)

Yeah, the MIDIMon is actually the main thing I made that for, but not for the LCD data monitor. I want to mess with some of Thorsten's seven segment code and matrix displays, and learn about the shift register handling for it. :)

I'll likely be using it with no LCD for that stuff, but will have one around for the inevitable "emergencies". :-[

It's got a few pin headers on the bottom for the d.in/out and a.in mux lines, and a jumper block to hold the Bank A lines @5v, or take them to external pots or whatever. The LCD socket is just a cheap 16pin DIP socket, cut in half. I bottom-soldered it with the pins set a bit high, so I could get to the joints (still a PITA), then hot melt glued around it so it couldn't move. Afterward, of course, I realize that my backlight pins don't go +/- for 15&16, so I have to cut into the glue, shave out a couple traces, and jump them back in reverse. Is that a common occurrence with the last two pins on some LCD's (may be worth a note on the LCD wiring PDF)?

One of those high quality "long-legged" DIP sockets would be best for the trace side wiring, but I only had 14's here. >:(  I'm thinking of moving to one of those nice looking PCB mount female header sockets for the LCD (the ones that look like the end plug of an IDE ribbon), and moving to a double-sided board, mainly just for those LCD traces. The PIC pinning, and the LCD location I used, puts a bunch of them in a really inconvenient order, so I just ran most of the traces for varying lengths away from the LCD socket, horizontally, and terminated them with pad holes, which jump down to the correct PIC pins with short wires on the top. It takes a few jumpers, but they're in neat parallel rows and they're ultimately hidden by the PIC (as are a couple caps and resistors, IIRC. The double-sided LCD traces and female header would make that a lot easier, but I figured if it worked, and I could refine it a bit, someone else here might like to make one for something, and I don't know what most of you guys are doing for etching, or how much trouble D.S. boards would be. With D.S. traces there, you could land them directly over the area just inside the PIC socket legs and solder a short wire from top to bottom, almost as easily as laying a jumper.

Here's the bottom view:

Bottom.jpg

There's a DPDT slide switch and a pin2 ground jumper at the back, which will turn the MIDI jack from an input to an output, for unidirectional MIOS devices, once the PIC's contents are finalized. Output mode is actually a bi-directional dual pinning, where the outer two DIN socket pins carry the input lines (used with an adapter), or you can just run a standard MIDI cord for output only. I'm about to do a 5pin to 15pin male, for a direct gameport cable, and may also look into an LTC based "direct-to-COM" addition.

Still wondering about the 9V battery if anybody knows? There's a pin header for a 5v output, but it's post-regulator/filters, so maybe a couple holes somewhere else, for external battery wires would work.

does it fit in a box
Funny, I'd like to get it into something, so I can throw it in my bag, but don't want it that much bigger. I thought about slicing a small chunk of 2x4 in half, and drilling out the insides for a small case like you mentioned. I'd also like it to be able to stay in there while I use it, so I guess I'll need holes for the sockets. With the case in mind, it may also help to move the four mounting holes out a bit, with some empty border area, so it could screw down flat on something. Otherwise, I can always stick a couple scraps of foam on it, or wrap it in cloth, and secure it with a rubberband.

Sad part is, I now have a whole batch of portable MB devices I made, so I can carry them around and play with MIOS/app assembler code, and so far, I don't appear to be carrying around anything. 8)

I was also thinking of doing modular "stacked" boards, with a header block at one end, and maybe a couple spacers on the other, along with a matching female socket on the bottom. That way, you could squash together a whole "brick" of core/d.in/d.out/a.in's, or whatever, maybe with those five pin 90 degree headers on their edges for any external part connections. I guess a socketed PIC, or the heatsink/caps, might get in the way there, unless you used a taller "link" socket or pin header on the core, or a regular external LCD/cable with the PIC on top, or you could take the main core link to the first board with a short ribbon and 90 degree dual row headers on the edge. ???

BTW-- Anyone think the heat of a small box-enclosed core is worth considering? I thought about putting some extra room on the sides of the regulator, maybe for the option of using those "fancy-finned", "bat" looking heat sinks.

Also, I might add a few easier direct connections, for a small number of optional buttons (or maybe even LED's). Right now, it just has the usual (2) MIDIMon buttons, which pull the first couple Bank A lines to ground, and I left out the ICSP stuff (I'll probably want that).

Can those two (or more) buttons on Bank A be easily configured to control the same MIOS functions of a regular "D.In" input, by shorting to ground on closure like that? It would help if I could work on button code without extra traces, boards, or shift registers, but I don't want to work with code which will require a bunch of repatching to use in a regular box.

Thanks!

George

PS- @BpM- Sorry for the thread hijack, but I guess they've already shot down the inverted LCD idea. ;)   

         

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Can those two (or more) buttons on Bank A be easily configured to control the same MIOS functions of a regular "D.In" input, by shorting to ground on closure like that? It would help if I could work on button code without extra traces, boards, or shift registers, but I don't want to work with code which will require a bunch of repatching to use in a regular box.

yes, just take the MIDImon application as an example. In j5_din.inc, function USER_J5_DIN_NotifyToggle you could branch directly to USER_DIN_NotifyToggle, it has the same parameter interface. By adding an offset to WREG and MIOS_PARAMETER1 (e.g. 0x80), the buttons will get their own unique IDs. But so long no DIN modules are connected, you don't need to take care about this (the ID is 0x00..0x07)

Best Regards, Thorsten.

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@Moebius- Is that a verification that the character display chips are indeed only set to support a fixed group of characters? (just wondering)

Yes, HD44780 and its "clones" have internally programmed character set (with HD44780U having slightly extended set). There's possibility to program 8 5x8dot characters in the internal ram inside the chip and these can be "re-programmed" on the fly by the driving application.

Moebius

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