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Darksoft

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This makes me wonder if other LCDs could be "hacked" for better resolution support, or even to bypass some image processing for lower lag.
I'm completely sure about it. You just need to dig a little bit on the firmwares, dump them, compare the, etc.

I'm pretty sure that at the end only a bunch of companies are doing the LCDs, so many firmwares must be compatible with each other.
 

defor

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BTW THANKS MAN..
sigh.

just spent the last few hours digging for the g-probe and g-wizard software that's used to program the Genesis based monitors.
I think i've got a pretty good idea of what we need to at least poke around with, but I need to actually get the software up and running... assuming I have all the bits...

It's really fun trying to track down software well after a company is dead and buried...
 

Darksoft

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I can imagine.....

Please post your findings! If we can get more monitors to run 25Khz that would be awesome.
 

defor

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seems that the tools I got weren't what i was looking for.. damn.

So, from the datasheet: http://igorx.irk.ru/datasheet/4rtlyRzj2F9U0q0ljTN9.pdf

To program the gm5221 the content of the external ROM is generated using Genesis softwaredevelopment tools G-Wizard and OSD-Workbench. G-Wizard is a GUI-based tool for capturing systeminformation such as panel timing, support modes, system configuration, etc. OSD-Workbench is a GUIbased tool for defining OSD menus and functionality.

Genesis recommends using Paradigm compiler (http://www.devtools.com) to compile the firmwaresource code into a hex file. This hex file is then downloaded into the external ROM using In-System-Programming (Genesis debug software G-Probe communicates with the OCM which in turn programs aFLASH ROM in the system using the ROM_WEn signal) or using commercially available ROMprogrammers.

gm5221 is equipped with an embedded ROM bootstrap function from which to boot when external ROMis not present or it does not contain data. It is always recommended to boot from embedded ROM (seedescription of ROM_ADDR16 in Table 16).

The bootstrap function works in the following way. The embedded ROM firmware first looks for a‘signature’ in external ROM (either parallel ROM or serial ROM depending on the programming ofROM_ADDR15 – see Table 16). The ‘signature’ is the ASCII values for the character string “xROM”starting at address 0x800F0. If this signature is found then it performs a CRC check. If CRC is valid thenit jumps to external ROM address 0x80100.

If the signature is not present (or bootstrap value of ROM_ADDR7 is one) then the embedded firmwaredoes not jump to external ROM. In this case it runs in its own loop that supports debugging commands(using G-Probe debugging software available from Genesis) over either the UART port (see section4.13.6) or the DDC2Bi port (see section 4.13.5).

The gm5221 has hardware to program FLASH ROM devices. In particular, the ROM_WEn pin can beconnected to the write enable of the FLASH ROM. The embedded boot firmware (see section 4.13.2above) performs the writes.

The gm5221 OCM has an integrated Universal Asynchronous Remote Terminal (UART) port that can beused as a factory debug port. In particular, the UART can be used to 1) read / write chip registers, 2) read/ write to NVRAM, and 3) read / write to FLASH ROM (In-System-Programming).

Hardware support is provided for DDC2Bi communication over the DDC channel of either the analog orDVI input ports. The specification for the DDC2Bi standard can be obtained from VESA(www.vesa.org). The DDC2Bi port can be used as a factory debug port or for field programming. Inparticular, the DDC2Bi port can be used to 1) read / write chip registers, 2) read / write to NVRAM, and3) read / write to FLASH ROM (In-System-Programming).
The factory programming or test station connects to the gm5221 through the Direct Data Channel (DDC)of the DSUB15 or DVI connectors. For example, the PC can make gm5221 display test patterns (seesection 4.5). A camera can be used to automate the calibration of the LCD panel.
So, some rather interesting bits here...
I find it hilarious that you can apparently reprogram the controller from an attached pc- that sounds SUPER SECURE GOOD JOB GUYS...
 

Derick2k

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Thats a rampart problem in the electronics industry. A lot of companies to cut cost would us dev boards and the like at times with the same demo circuits the manufacturer of the board had designed. They would save $$ byt not having the circuit/board custom designed and manufactured. Any code on the chips would not even be secured most of the time. You could just clip onto the board and reprogram it without issues. I used to due repair work back in the day, you would be amazed at the stuff I used to find. BTW, programmers are always cute, leaving little easter eggs and other crap in the program code. Always fun to find those.
 

defor

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Thats a rampart problem in the electronics industry. A lot of companies to cut cost would us dev boards and the like at times with the same demo circuits the manufacturer of the board had designed. They would save $$ byt not having the circuit/board custom designed and manufactured. Any code on the chips would not even be secured most of the time. You could just clip onto the board and reprogram it without issues. I used to due repair work back in the day, you would be amazed at the stuff I used to find. BTW, programmers are always cute, leaving little easter eggs and other crap in the program code. Always fun to find those.
worst case, we can probably disassemble it and see what's actually going on somewhat or add some tweaks, etc.
 

defor

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Dumped all three versions I have- I was able to successfully convert both the 1.1.12 and the 1.2.05 boards into a 1.1.10 as expected.
Also I've noticed that the 1.2.05 I got was a BK2, while the 1.1.12 was a BK1- there are some significant changes to the case design and interior shielding between the models... Just interesting...
Anyway- here's the rom dumps so that you can reprogram your own if you see fit:

Verified GOOD:
F/W ID C59SLP10
F/W VER. 1.1.10
View attachment NEC_LCD1970NX_1.1.10_C59SLP10.zip



Verified BAD:
F/W ID C39SAP10
F/W VER. 1.1.12
View attachment NEC_LCD1970NX_1.1.12_C39SAP10.zip



F/W ID CB9SSP10
F/W VER. 1.2.05
View attachment NEC_LCD1970NX_1.2.05_CB9SSP10.zip
 

Mitsurugi-w

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Defor,

I'm looking to buy one on ebay but it looks like there are two significantly different main boards for these. One has vga and DVI and I think 3 usb ports. The other looks like 4 usb ports and component plugs.

Can either be converted in this way?
 

Darksoft

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I'm kind of surprised people worried about the 15Khz. ALL monitors that have a SCART connector will support 15Khz, at least here in Europe. I guess that people are more concerned about the VGA connector to support 15Khz as well, so they don't have to have 2 cables for computers like AMIGA.

I'm only interested on 24Khz replacement for cabinet, not test bench, so I guess I'll end up either buying one of these Makvision or buying one of these highscalers, which I heard can do the job.

http://www.ebay.es/itm/HD9800-Video...268761?hash=item27fde37c99:g:g30AAOSwfcVUFkf-
 

twistedsymphony

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ALL monitors that have a SCART connector will support 15Khz, at least here in Europe
The problem is that SCART connectors are ONLY in Europe. Here in the states RGB capable monitors and TVs are extremely rare. Basically your options are either arcade monitors, or professional broadcast monitors from old TV and Movie studios.... so when it's discovered that a normal consumer display has an RGB option it is very valuable information.
 

Darksoft

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ALL monitors that have a SCART connector will support 15Khz, at least here in Europe
The problem is that SCART connectors are ONLY in Europe. Here in the states RGB capable monitors and TVs are extremely rare. Basically your options are either arcade monitors, or professional broadcast monitors from old TV and Movie studios.... so when it's discovered that a normal consumer display has an RGB option it is very valuable information.
I see.

Anyways, did someone tried 24Khz games on that Chinese Upscaler/Video Frequency converter?

http://www.ebay.es/itm/HD9800-Video...268761?hash=item27fde37c99:g:g30AAOSwfcVUFkf-
 

SNK-NEO-GEO

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Fudoh at SHMUPS has a good review of the OCC.. Once I am back home I will search and post the link.. Basically is somewhere between the xrgb3 and the nimi.

Found it:)
http://retrogaming.hazard-city.de/ossc.html

What Fudoh said is that the OCCC and a DVDO is as good as it gets.. The DVDO only adds 6ms of lag.. The mini adds 24ms lag.

I tested a xrgb3 and Those are not plug and play, pain in the ass to get a steady picture.. The mini is basically plug and play but that 24ms of lag:(
 
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Derick2k

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Guys I got that LCD, what is the best method to test it, with PC, motherboard/game?? Does the naomi with or without a game loaded have a way to test resolutions/rates. Everything else I have in storage at the moment. Can I test with a PC, but I guess i would need an old video card for that.
 

twistedsymphony

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NAOMI in 15K mode
System 256 in 15K mode
Sega Model 3

these all have VGA ports with separate HV sync that you can plug in and test low resolutions.

To use a PC you'd need a ATi Card with CRT_EmuDriver.
 
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