Author Topic: SLG3000 Scanline Generator performs  (Read 23403 times)

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
SLG3000 Scanline Generator performs
« on: March 07, 2011, 05:28:19 am »
SLG3000 Scanline Generator Review and Demo

He's got a few good videos covering a few bits and bobs ,cga to vga scaler and the like.For me ,xrgbs aren't need now.

Offline ニユ-マン

  • MassiveMember
  • ****
  • Posts: 233
Re: SLG3000 Scanline Generator performs
« Reply #1 on: March 22, 2011, 04:50:59 am »

The SLG3000 costs 49Euro, but  a clever Korean found a way to do the same thing for a few cents  ;D




It's only missing the 3 trimmers to adjust the level.


The author of the discovery is Sharksym, and his webpage with photos is here:
http://sharksym.egloos.com/4930096


Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #2 on: March 24, 2011, 05:19:43 am »
AWESOME !
The capacitors on each ic,are they just smoothing/bypass ones?
« Last Edit: March 24, 2011, 05:34:34 am by bigsanta »

Offline hellbelly

  • BigMember
  • ***
  • Posts: 67
    • mmmonkey
Re: SLG3000 Scanline Generator performs
« Reply #3 on: March 28, 2011, 04:09:03 am »
Has anyone on here tried the DIY scanline generator yet?

Offline hellbelly

  • BigMember
  • ***
  • Posts: 67
    • mmmonkey
Re: SLG3000 Scanline Generator performs
« Reply #4 on: April 07, 2011, 08:33:52 am »
Parts arrived today to do the DIY Scanline mod.  I knocked it up but I don't have my RGB to VGA scaler yet.  So here's a quick screenshot with my Dreamcast outputting VGA (couldn't find the best game to show it off either!)






« Last Edit: April 07, 2011, 08:40:53 am by hellbelly »

Offline SignOfZeta

  • SmallMember
  • **
  • Posts: 9
Re: SLG3000 Scanline Generator performs
« Reply #5 on: April 09, 2011, 03:32:15 am »
Well, that looks pretty great. It bet it would go well with Street Fighter III.

With the scanlines being non-adjustable...what is the theory here? Would they default to something like "max" on an SLG3000? If so, that's perfect since that's where I'd leave it anyway. From the image though they look like they could be a bit thicker for my tastes...

I'll have to get some parts and try this.

Offline hellbelly

  • BigMember
  • ***
  • Posts: 67
    • mmmonkey
Re: SLG3000 Scanline Generator performs
« Reply #6 on: April 22, 2011, 07:36:17 am »
Just added the DIY job to a cheap upscaler, I really like it

 

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #7 on: May 23, 2011, 11:03:11 pm »

The SLG3000 costs 49Euro, but  a clever Korean found a way to do the same thing for a few cents  ;D




It's only missing the 3 trimmers to adjust the level.


The author of the discovery is Sharksym, and his webpage with photos is here:
http://sharksym.egloos.com/4930096



Something i've never asked ,but exactly how are the ICs making the black scan lines .How's it done ?

Offline ニユ-マン

  • MassiveMember
  • ****
  • Posts: 233
Re: SLG3000 Scanline Generator performs
« Reply #8 on: May 24, 2011, 02:37:41 am »

IC1A changes state with every HSync pulse, so one line is untouched and the next one is blanked (or vice-versa).
The switch (S1) selects if the blanking circuit (IC2) has to erase the even or the odd lines.
When IC2 is active the RGB lines are grounded and you see a black line.

Would they default to something like "max" on an SLG3000?
Yes

Quote
From the image though they look like they could be a bit thicker for my tastes...

You can't have thicker scanlines with this method, you are already discarding 50% or your image...


Offline Tiido Priimägi

  • MassiveMember
  • ****
  • Posts: 232
  • Mega Drive Modding Master
    • Tiido's QB45 & MD site
Re: SLG3000 Scanline Generator performs
« Reply #9 on: May 25, 2011, 08:51:33 pm »
Haha, the simple scanline generator is so ingenious :D
Mida sa loed ? Nagunii aru ei saa ;)

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #10 on: May 31, 2011, 09:04:36 am »
Unused inputs on the 7474 should be tied high or low,don't leave them floating.

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #11 on: June 04, 2011, 02:40:26 am »

IC1A changes state with every HSync pulse, so one line is untouched and the next one is blanked (or vice-versa).
The switch (S1) selects if the blanking circuit (IC2) has to erase the even or the odd lines.
When IC2 is active the RGB lines are grounded and you see a black line.

Would they default to something like "max" on an SLG3000?
Yes

Quote
From the image though they look like they could be a bit thicker for my tastes...

You can't have thicker scanlines with this method, you are already discarding 50% or your image...


Do you have an idea how the SLG3000 operates then ?

Offline hellbelly

  • BigMember
  • ***
  • Posts: 67
    • mmmonkey
Re: SLG3000 Scanline Generator performs
« Reply #12 on: June 05, 2011, 07:16:51 pm »

IC1A changes state with every HSync pulse, so one line is untouched and the next one is blanked (or vice-versa).
The switch (S1) selects if the blanking circuit (IC2) has to erase the even or the odd lines.
When IC2 is active the RGB lines are grounded and you see a black line.

Would they default to something like "max" on an SLG3000?
Yes

Quote
From the image though they look like they could be a bit thicker for my tastes...

You can't have thicker scanlines with this method, you are already discarding 50% or your image...



Thanks for the explanation and the diagram of how to make it, I appreciate it.  I really like the scanlines this produces, and hope to buy an SLG3000 one day as a comparison of the images and to see what the extra options are like on my TV.

Offline Telis

  • SmallMember
  • **
  • Posts: 12
Re: SLG3000 Scanline Generator performs
« Reply #13 on: June 17, 2011, 07:02:37 am »
Hi, i follow this circuit diagram but don´t work here, only Black Screen  :(

PIN #4 is VCC +5V? the 74LS74 datasheet PIN#14 is VCC.
74LS125 don´t need VCC?
The RGB IN PIN#1,2,3 are connected directly to RGB OUT PIN#1,2,3 together with PIN#3,6,8 74LS125?

IF, someone has a more detailed diagram of the circuit please PM.

TNKS  ;D

Offline hellbelly

  • BigMember
  • ***
  • Posts: 67
    • mmmonkey
Re: SLG3000 Scanline Generator performs
« Reply #14 on: June 17, 2011, 07:15:13 am »
The diagram assumes that you are going to power the chips so hasn't labelled it.  So yes, on the 74ls74 you need  14 - VCC and also leg 4, then GND to leg 7.  The 74ls125 expects VCC on leg 14, GND on 7 (as well as 2, 5 and 9)

bigsanta has also pointed out that the unused inputs on 74ls74 should be grounded which I haven't tried yet.

Then wiring up the RGB and H and V Sync is just attaching the labelled legs, with the relevant pins on VGA - 1, 2, 3, 13 and 14

Pete


Offline Telis

  • SmallMember
  • **
  • Posts: 12
Re: SLG3000 Scanline Generator performs
« Reply #15 on: June 17, 2011, 07:34:29 am »
The diagram assumes that you are going to power the chips so hasn't labelled it.  So yes, on the 74ls74 you need  14 - VCC and also leg 4, then GND to leg 7.  The 74ls125 expects VCC on leg 14, GND on 7 (as well as 2, 5 and 9)

bigsanta has also pointed out that the unused inputs on 74ls74 should be grounded which I haven't tried yet.

Then wiring up the RGB and H and V Sync is just attaching the labelled legs, with the relevant pins on VGA - 1, 2, 3, 13 and 14

Pete



Thanks for the help.

I will try this tomorrow and post the results.  ;)

Offline Telis

  • SmallMember
  • **
  • Posts: 12
Re: SLG3000 Scanline Generator performs
« Reply #16 on: June 18, 2011, 04:09:04 am »
The diagram assumes that you are going to power the chips so hasn't labelled it.  So yes, on the 74ls74 you need  14 - VCC and also leg 4, then GND to leg 7.  The 74ls125 expects VCC on leg 14, GND on 7 (as well as 2, 5 and 9)

bigsanta has also pointed out that the unused inputs on 74ls74 should be grounded which I haven't tried yet.

Then wiring up the RGB and H and V Sync is just attaching the labelled legs, with the relevant pins on VGA - 1, 2, 3, 13 and 14

Pete




Thanks for the help.

I will try this tomorrow and post the results.  ;)



Hi folks  :D

Well. it´s WORKS now  ;D Thank you Pete

PS2 using S-video cable and a cheap S-video To Vga converter at 1024x768, this converter can´t handle 640x480  :'(. In my tests this scanline generator offers a good scanlines using 640x480 , 800x600 scanlines don´t work and 1024x768 works but scanlines is not good. I´m wainting my new video converter to test via Component and 640x480 output.




Now..... how can i control the scanlines intensity??

Thank you folks and pete.

Sorry for my english and my cam.  ;)
« Last Edit: June 22, 2011, 12:45:48 pm by Telis »

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #17 on: June 21, 2011, 12:26:55 am »
I don't think it's possible with this circuit.

Only with the slg3000
http://shmups.system11.org/viewtopic.php?f=6&t=33454
« Last Edit: June 21, 2011, 12:29:32 am by bigsanta »

Offline gojirien

  • SmallMember
  • **
  • Posts: 10
Re: SLG3000 Scanline Generator performs
« Reply #18 on: June 21, 2011, 06:41:05 am »
Hi, long time  I haven't logged on this forum ! I have just wired my cga/vga converter (using chinese cga/ega to vga converter) + slg3000.

I want to try the diagrams showed on this thread, they're very interesting.

Are you sure that scanlines intensity cannot be controlled ? I thought using triple potentiometer (500 ohm, like piher pt10 used on the slg3000) would be ok, putting one after HD74LS125.

I'm not good in electronics, it's just a question  :).

Offline Telis

  • SmallMember
  • **
  • Posts: 12
Re: SLG3000 Scanline Generator performs
« Reply #19 on: June 21, 2011, 07:00:14 am »
Hi, long time  I haven't logged on this forum ! I have just wired my cga/vga converter (using chinese cga/ega to vga converter) + slg3000.

I want to try the diagrams showed on this thread, they're very interesting.

Are you sure that scanlines intensity cannot be controlled ? I thought using triple potentiometer (500 ohm, like piher pt10 used on the slg3000) would be ok, putting one after HD74LS125.

I'm not good in electronics, it's just a question  :).

Hi.
I put a single potentiometer "100 ohms"  between the switch and it did not work. Adjusting the visibility of the black line at 50% OR reducing its thickness would be fantastic.

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #20 on: June 21, 2011, 07:01:38 am »
Hi, long time  I haven't logged on this forum ! I have just wired my cga/vga converter (using chinese cga/ega to vga converter) + slg3000.

I want to try the diagrams showed on this thread, they're very interesting.

Are you sure that scanlines intensity cannot be controlled ? I thought using triple potentiometer (500 ohm, like piher pt10 used on the slg3000) would be ok, putting one after HD74LS125.

I'm not good in electronics, it's just a question  :).


IC1A changes state with every HSync pulse, so one line is untouched and the next one is blanked (or vice-versa).
The switch (S1) selects if the blanking circuit (IC2) has to erase the even or the odd lines.
When IC2 is active the RGB lines are grounded and you see a black line.

Would they default to something like "max" on an SLG3000?
Yes

Quote
From the image though they look like they could be a bit thicker for my tastes...

You can't have thicker scanlines with this method, you are already discarding 50% or your image...



Offline gojirien

  • SmallMember
  • **
  • Posts: 10
Re: SLG3000 Scanline Generator performs
« Reply #21 on: June 21, 2011, 05:48:36 pm »
Thank you Telis and Bigsanta for answer. I didn't read ニユ-マン's post carefully, sorry.

I'm currently investigating my slg3000, it has a Texas Instruments ship (red circle on picture) which seems to have same function as the HD74LS74 if I'm not wrong. It has 3 more ICs labelled "JATR" (green circles). I'm not sure of the TI IC's reference, I think it is CDHC73MG4. I haven't found datasheet for the 3 more little ICs yet.




Offline ニユ-マン

  • MassiveMember
  • ****
  • Posts: 233
Re: SLG3000 Scanline Generator performs
« Reply #22 on: June 22, 2011, 08:55:42 am »
Unused inputs on the 7474 should be tied high or low,don't leave them floating.

I'm not sure, but I think it MUST be done only for CMOS parts, the proposed circuit uses LS parts so it can be facultative...
Anyway I just wanted to point out that in Telis's circuit the outputs of the '74 ( pin 8 & 9) are both connected to GND which I don't think it' a good practice.

I thought using triple potentiometer (500 ohm, like piher pt10 used on the slg3000) would be ok, putting one after HD74LS125.

It won't work, this circuit is totally digital, it can only do on/off.
To do what you want you'll have to replace the '125 with an analog circuit (for example an op-amp).

800x600 scanlines don´t work and 1024x768 works but scanlines is not good. I´m wainting my new video converter to test via Component and 640x480 output.
I found this table with the timings of the VGA modes:

Mode       Horiz  Vertical  Horiz  Vert  Horiz  HSYNC  Vertical VSYNC
           Dots   Lines     KHz    Hz    Sync   Pol    Sync     Pol
VGA-480     640   480       31.5   60    3.8 us  -      64 us    -
VGA-400     640   400       31.5   70    3.8 us  -      64 us    +
SVGA I      800   600       35.2   56    2.0 us  -      57 us    -
SVGA II     800   600       37.8   60    3.2 us  +     106 us    +
SVGA III    800   600       48.0   72    2.4 us  +     125 us    +
XGA        1024   768       48.5   60    2.0 us  -     124 us    


As you can see both the SVGA@60  and SVGA@72 modes use positive pulses for the Hsync, maybe that's why it doesn't work.
« Last Edit: June 22, 2011, 08:57:59 am by ニユ-マン »

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #23 on: June 22, 2011, 10:25:37 am »
The diagram assumes that you are going to power the chips so hasn't labelled it.  So yes, on the 74ls74 you need  14 - VCC and also leg 4, then GND to leg 7.  The 74ls125 expects VCC on leg 14, GND on 7 (as well as 2, 5 and 9)

bigsanta has also pointed out that the unused inputs on 74ls74 should be grounded which I haven't tried yet.

Then wiring up the RGB and H and V Sync is just attaching the labelled legs, with the relevant pins on VGA - 1, 2, 3, 13 and 14

Pete




Thanks for the help.

I will try this tomorrow and post the results.  ;)



Hi folks  :D

Well. it´s WORKS now  ;D Thank you Pete

Can i upload a more detailed circuit diagram? Here...



PS2 using S-video cable and a cheap S-video To Vga converter at 1024x768, this converter can´t handle 640x480  :'(. In my tests this scanline generator offers a good scanlines using 640x480 , 800x600 scanlines don´t work and 1024x768 works but scanlines is not good. I´m wainting my new video converter to test via Component and 640x480 output.




Now..... how can i control the scanlines intensity??

Thank you folks and pete.

Sorry for my english and my cam.  ;)

Pins 8 and 9 of the 7474 are outputs,so leave them unconnected.

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #24 on: June 22, 2011, 10:28:41 am »
Unused inputs on the 7474 should be tied high or low,don't leave them floating.

I'm not sure, but I think it MUST be done only for CMOS parts, the proposed circuit uses LS parts so it can be facultative...
Anyway I just wanted to point out that in Telis's circuit the outputs of the '74 ( pin 8 & 9) are both connected to GND which I don't think it' a good practice.

I thought using triple potentiometer (500 ohm, like piher pt10 used on the slg3000) would be ok, putting one after HD74LS125.

It won't work, this circuit is totally digital, it can only do on/off.
Using a hc version of the 7474 ,i've always been told to tie unused inputs,so just assumed the same for LS versions.
To do what you want you'll have to replace the '125 with an analog circuit (for example an op-amp).

800x600 scanlines don´t work and 1024x768 works but scanlines is not good. I´m wainting my new video converter to test via Component and 640x480 output.
I found this table with the timings of the VGA modes:

Mode       Horiz  Vertical  Horiz  Vert  Horiz  HSYNC  Vertical VSYNC
           Dots   Lines     KHz    Hz    Sync   Pol    Sync     Pol
VGA-480     640   480       31.5   60    3.8 us  -      64 us    -
VGA-400     640   400       31.5   70    3.8 us  -      64 us    +
SVGA I      800   600       35.2   56    2.0 us  -      57 us    -
SVGA II     800   600       37.8   60    3.2 us  +     106 us    +
SVGA III    800   600       48.0   72    2.4 us  +     125 us    +
XGA        1024   768       48.5   60    2.0 us  -     124 us    


As you can see both the SVGA@60  and SVGA@72 modes use positive pulses for the Hsync, maybe that's why it doesn't work.


I've always been told to tie unused inputs ,never leave them floating .
« Last Edit: June 23, 2011, 11:59:33 pm by bigsanta »

Offline Telis

  • SmallMember
  • **
  • Posts: 12
Re: SLG3000 Scanline Generator performs
« Reply #25 on: June 22, 2011, 12:44:36 pm »
Hi folks.

Thanks for the information, i will remove the PIN´s #8 and #9 from ground and update the diagram.

Hey this table you posted is very interesting.

Here more samples from true VGA output

VGA 640x480 (original)


VGA 640x480 (scanlines)


VGA 800x600 (scanlines) decrease the screen brightness by 50% and does not generate the scanlines, the screen is very dark.


VGA 1024x768 (scanlines) When put this mode you hardly notice the scanlines, I'm starting to like this resolution. The picture becomes softer, the first time i was tested at 1024x768 was on 19" LCD monitor, now i did the test on my TV 32" LCD 1024x768 and looks great, I changed my opinion.


UPDATED DIAGRAM:

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #26 on: June 23, 2011, 06:17:08 am »
One more thing.
I'm using a 74hc74n and a 74ls125n and i have no 5Vcc power supply connected to the chips power pin (14) or pin 4 of the 7474 ,but it is powered just from the vga cable's output ,same with the chip's Vss/gnd pins and all other Vss/gnd connections.Both chips are getting power that is well below what their data sheets recommend .And the finished circuit is now installed inside of a 2 port vga switcher.

Try it on a solderless breadboard  (with everything wired as in my wiring diagram ,but without connecting power to the Vcc pins )and check the voltage being received ,well below 4 volts.(also with all unused inputs on the 74hc74 left unconnected)


« Last Edit: July 02, 2011, 11:21:03 pm by bigsanta »

Offline Telis

  • SmallMember
  • **
  • Posts: 12
Re: SLG3000 Scanline Generator performs
« Reply #27 on: June 24, 2011, 08:06:40 am »
Interesting, mine HD74LS74AP does not work without the 5v power  ::)


Offline Moosmann

  • MassiveMember
  • ****
  • Posts: 146
    • http://playoffline.wordpress.com/
Re: SLG3000 Scanline Generator performs
« Reply #28 on: June 25, 2011, 05:39:35 pm »
Quote
I haven't found datasheet for the 3 more little ICs yet.

"JATR" is not the IC Part Description/Number, it is only the SMD Code. The SLG-3000 (with adjustable scanline intensity) works difference compare the self-build Scanline Generator. I will make a 1:1 SLG-3000 clone next weekend (for my self-use, mostly for other applications). Unfortunately, I cannot offer a circuit diagramm for the SLG-3000 without permission from the original designer.

Greetings Markus

Offline ニユ-マン

  • MassiveMember
  • ****
  • Posts: 233
Re: SLG3000 Scanline Generator performs
« Reply #29 on: June 25, 2011, 09:08:15 pm »
Moosmann,

Can you tell if the problems in the 800x600  mode are caused by the inversed sync polarity?

Also do you think a circuit like this would work for variable intensity scanlines:



  (Switch enable signal from '74)   
                       |
                       |
         +-------/ -----+                           <-- Analog bilateral switch with enable input as the  74LVc1G66
         |                        |
         |                        |
IN --+-/\/\/\/\---+--- OUT            <-- Potentiometer
         |            ^                                
         |             |                                     
         +-------+                                     
74LVc1G66 Datasheet > http://www.nxp.com/documents/data_sheet/74LVC1G66.pdf



Offline Moosmann

  • MassiveMember
  • ****
  • Posts: 146
    • http://playoffline.wordpress.com/
Re: SLG3000 Scanline Generator performs
« Reply #30 on: June 26, 2011, 12:54:01 am »
Quote
Can you tell if the problems in the 800x600  mode are caused by the inversed sync polarity?

I can tell you this in the next 1-2 Weeks.

Quote
lAlso do you think a circuit like this would work for variable intensity scanlines

You answer your own question;)

Greetings Markus

Offline gojirien

  • SmallMember
  • **
  • Posts: 10
Re: SLG3000 Scanline Generator performs
« Reply #31 on: July 01, 2011, 11:01:09 pm »
Hi, Just made the scanline circuit with 74LS74 and 74LS125. I have made the same mod that Bigsanta, with a cga/ega/vga converter.

Scanlines work perfectly, but I have a background "grid" on the screen, it's tight but I don't like it, and I don't have this grid with slg3000.

If someone knows a solution (grounding problem maybe ?).

Offline Telis

  • SmallMember
  • **
  • Posts: 12
Re: SLG3000 Scanline Generator performs
« Reply #32 on: July 02, 2011, 01:14:29 am »
Hi, Just made the scanline circuit with 74LS74 and 74LS125. I have made the same mod that Bigsanta, with a cga/ega/vga converter.

Scanlines work perfectly, but I have a background "grid" on the screen, it's tight but I don't like it, and I don't have this grid with slg3000.

If someone knows a solution (grounding problem maybe ?).

Hi. This happens at any Resolution? Can you post a picture using this DIY Scanline and SLG3000 for comparison?

Thanks

Offline gojirien

  • SmallMember
  • **
  • Posts: 10
Re: SLG3000 Scanline Generator performs
« Reply #33 on: July 03, 2011, 12:58:39 am »
Hi, I have the background with 640*480, scanlines circuit doesn't work at any other resolution.

Here is the background grid with scanlines circuit :



And on that picture, use of the slg3000, screen is fine black, no background :



Also, ingame comparison :

Scanlines circuit :


Slg3000 :


With the scanlines circuit we can see vertical lines on the picture.

Offline Telis

  • SmallMember
  • **
  • Posts: 12
Re: SLG3000 Scanline Generator performs
« Reply #34 on: July 03, 2011, 09:53:57 am »
I do not see vertical lines, but image is similar to images with interference.

You've checked all the wires are OK?


Offline gojirien

  • SmallMember
  • **
  • Posts: 10
Re: SLG3000 Scanline Generator performs
« Reply #35 on: July 03, 2011, 10:08:06 pm »
All wires are ok, I'm wondering about chips quality, or if I have damaged them during soldering. I'll try next with sockets for the 74 chips.

Take a look on the follonwing picture, on the bottom left you can see vertical lines :


Offline hellbelly

  • BigMember
  • ***
  • Posts: 67
    • mmmonkey
Re: SLG3000 Scanline Generator performs
« Reply #36 on: July 06, 2011, 02:03:25 am »
Which scaler are you using, the 2 VGA or one VGA model?  I ask as my 2VGA model puts horizontal lines on the image with this scanline mod when using the VGA out that's close to the edge of the board, but it fine when using the middle vga out.  (I haven't investigated this further yet, it might just be the placement of the scanline board when I stuck it on the underside of the scalers board)

Pete

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #37 on: July 09, 2011, 10:12:58 am »
JATR  

JA = some type of high speed diode
T= where it's made ? malaysia
R=?

From the smd codebook
http://www.marsport.org.uk/smd/mainframe.htm

CODE               DEVICE NAME  
 JA                           BAV74        dual sw diodes
                                                      
 JA                           BAV74        dual diode cc 50V 0.1A

Obviously it can't be either of those ,as they're 3 pin ICs,but these JATR coded smd ICs on the slg3000 ,i think there were originally 6 pins ,but have had the middle pin snapped off (look closely at them, using a jewelers magnifier or something similar ) and you can see the remains of what looks like a leg  .
« Last Edit: July 09, 2011, 11:43:46 am by bigsanta »

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #38 on: July 09, 2011, 11:54:02 am »
Moosmann,

Can you tell if the problems in the 800x600  mode are caused by the inversed sync polarity?

Also do you think a circuit like this would work for variable intensity scanlines:



 (Switch enable signal from '74)   
                       |
                       |
         +-------/ -----+                           <-- Analog bilateral switch with enable input as the  74LVc1G66
         |                        |
         |                        |
IN --+-/\/\/\/\---+--- OUT            <-- Potentiometer
         |            ^                               
         |             |                                      
         +-------+                                    
74LVc1G66 Datasheet > http://www.nxp.com/documents/data_sheet/74LVC1G66.pdf





That's what those 3  smd JATR coded  ICs are ,aren't they  :D as they seem to be pin for pin connected on the slg3000 pcb
« Last Edit: July 09, 2011, 12:07:56 pm by bigsanta »

Offline bigsanta

  • MassiveMember
  • ****
  • Posts: 254
Re: SLG3000 Scanline Generator performs
« Reply #39 on: July 09, 2011, 12:55:07 pm »
Thank you Telis and Bigsanta for answer. I didn't read ニユ-マン's post carefully, sorry.

I'm currently investigating my slg3000, it has a Texas Instruments ship (red circle on picture) which seems to have same function as the HD74LS74 if I'm not wrong. It has 3 more ICs labelled "JATR" (green circles). I'm not sure of the TI IC's reference, I think it is CDHC73MG4. I haven't found datasheet for the 3 more little ICs yet.





CD74HC73
The 7473 is just a positive edge dual D type flip flop , where as the slg3000 flip flop seems to be a dual JK negative triggered one .I think only 1 flip flop is being used .But if the slg3000 is using an analog switch which needs E to be active when high and thus Y and Z = on state ,then how come are Y and Z being read as  a closed switch instead of open/off  ,when the slg3000 is not connected to anything ?
« Last Edit: July 10, 2011, 11:17:32 am by bigsanta »