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MBHP TV (preview)


TK.
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How about

  • a big MTC display
  • a nice meter bridge
  • a CC parameter screen
  • a MIOS status display

on your TV?

mbhp_tv_preview.jpg

is coming soon :-)

Based on the Video HowTo from Rickard Gunee http://www.rickard.gunee.com/projects/

Schematic:

http://www.ucapps.de/mbhp/mbhp_tv.pdf

(you can just re-use your existing MBHP_CORE module and add the two resistors for the Video Out)

Preview firmware:

http://www.ucapps.de/tmp/mbhp_tv_preview.syx.zip

(only prints this intro on screen)

Specs:

standalone application, display accessible via MIDI, resolution: 128x64, black-white only, currently PAL only, NTSC planned.

Best Regards, Thorsten.

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This is so cool! It isn't some sort of joke is it? ;D

I can't help laughing at that pixelated screen ;D :D

But that makes it all the more cheazier ;)

yes, I'm glad I didn't throw away that amiga monitor!

(also brings back memories of the C64 ads, with cheezy wooden panneled '70's TV's :))

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Thanks! :)

I started the MBHP_TV as a new challenge to learn something new (e.g. to find a solution for an isochronous system which never gets out-of-sync), it's another topic if a display with such a low resolution is usefull or not. But it awakes some vintage feeling - if MIOS would support a keyboard and a mass storage device (PRESS PLAY ON TAPE...), you would have a complete homecomputer ;-)

The fascinating thing on this project is that you can see the execution time of a routine directly on screen. Every pixel "consists" of 4 PIC instructions executed within 400 nS - I could also display a pixel with one instruction only, but the PIC18F452 doesn't offer enough memory to store so much data.

However, the code is now released and can be found in the MIOS download section (still PAL only), the resolution is 128x64, only one  character set is supported yet (but additional fonts could be included) - character size 8x8 (16x8 display)

Following SysEx commands are available:

;    o Clear Screen:
;         f0 00 00 7e 3f 00 00 f7
;    o Set Cursor Pos and Print Characters:
;         f0 00 00 7e 3f 00 01 <pos> <char_1> <char_2> ... <char_n> f7
;    o Print Characters (don't set cursor):
;         f0 00 00 7e 3f 00 02 <char_1> <char_2> ... <char_n> f7

The MBHP_TV module will be supported by the next MIDIbox LC version :)

Best Regards, Thorsten.

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:-X ;D :-X ;D :-X ;D :-X ;D :-X ;D :-X ;D :-X ;D

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!DUDE!!!

***falls over***

hehehehe

my sequencer is gonna LOVE this. I love it!! I think I just officially stopped working on the UI hehehehehhee!!

TK, you're like....wow dude....That's pretty impressive :) So what's limiting the resolution anyway?

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Dan: you've to use the scart socket (A/V input of your TV)

Btw.: the next MIOS version will support a new display type #6 which redirects all print commands directly to the MIDI Out based on the new MBHP_TV protocol. By changing the device ID up to 128 "MLCDs" can be addressed in this way - not only the MBHP_TV itself, but also other "slaves" which support this protocol (example driver for a character LCD as slave will follow).

I also plan to include a "soft font" feature into the MBHP_TV which allows to create special characters dynamically like known from character LCDs - hold the line ;-)

Best Regards, Thorsten.

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TK you are a machine!!!!  :D

Btw.: the next MIOS version will support a new display type #6 which redirects all print commands directly to the MIDI Out based on the new MBHP_TV protocol. By changing the device ID up to 128 "MLCDs" can be addressed in this way - not only the MBHP_TV itself, but also other "slaves" which support this protocol (example driver for a character LCD as slave will follow).

I can see it now...rows and rows of TV screens displaying SID parameters, sequences, routing paths, control data.... ;D :P ;D *twitch* *twitch* I'm freaking out man!!

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Tried it out! Cooooooooooooool!!! ;D

But to things (just questions):

I read a little about this 2TV PIC on Rickards site and two things came to my mind:

First: Hey there is a gray scale, too! (just white, grey and black, but whatever) Can that be implemented into MIOS? Its just sending the signal to Port D1 and let D0 on mass. Possibility? But on the other hand: Usefull for MIOS? Perhaps...

Second: Rickard used a slow and little PIC16C84 with a 12 Mhz Oscilator. With a PIC18F (with lets say a 24 Mhz oscillator quadrupled to 48 Mhz) the signal would be sent four times as fast and so double the vertical and horizontal resolution (256x128!!!!! *freaking out again*), or not? Possible? To much work?

These are just some thoughts, but I`m just to hot about that TV thing!! So dammit cool!!!  :D

Wont sleep to much tonight!

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hehe I think I'm going to try this this afternood! :)

maybe with a faster pic... more resolution? :)

But, is anybody here who know the "minitel"? it's a french, old, phone terminal, with a small screen... maybe usefull as a MIOS screen (and cheaper than a tv)

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The resolution isn't limited by speed, but by the available RAM.

However, the next version will support a hires mode with quadrubled resolution which will only work with "ROM fonts" and with 1 pixel distance between the 8x8 characters. This will be nice as replacement for the MIDIbox LC display, since exactly 56 characters can be displayed per line in this way.

Grayscales: not possible since two pins cannot be stimulated at the same time when the shifting method (for highest speed) is used.

Best Regards, Thorsten.

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Guest den_Juin

<dreamer mode>

Maybe it's possible to implement a dedicated processor, so higher res, and maybe even colours could be possible.

</dreamer mode>

Anyway, keep up the good work TK, i see lots of potential in this new little gadget :D

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No I don't know the new album yet, but I will check it on the next trip through the CD store - thanks for the hint :)

Some words to the improved resolution: I haven't taken into account that storing so much characters per line also costs too much RAM. Another problem is the "tblrd" instruction which takes 2 cycles instead of one - very bad for "balanced code" (a requirement for proper graphics).

So a compromise would be an alternative mode with 40x25 ROM characters, and maybe another alternative mode which allows to split the screen in two halfs for a big and a small font. Let's check it next weekend ;-)

Best Regards, Thorsten.

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To prevent any rumours: For most applications this isn't true.

External RAM requires a completely different "core module" concept for an external bus interface. The realization is easy, but the circuit would be too complex for beginners (due to the increased number of connections) and much more expensive! It would limit the number of free PIC pins so that they would have to be replaced by multiplexers and latches, attached on the bus.

Since the effort for myself would be to high to support two different concepts, I will stay by the current solution and try to live with the limitations, hoping that Microchip releases new compatible derivatives with even more internal RAM in the next years.

However, external RAM won't help here, the access times are at least 10 cycles (possibly more, depends on the hardware design), this would result to a resolution of maybe 32x64 pixels ;-)

Expected resolution with internal memory (by using ROM fonts, I will try it this weekend): 300xYYY pixels (YYY only limited by the number of scanlines of your TV) -maybe more

For comparison the possible resolution if more internal RAM would be available: ca 580xYYY

But most TVs wouldn't be able to display it properly...

Best Regards, Thorsten.

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