According to Console5's pinouts, the CXA1801 has F Ok on pin 28 and it is also found on pin 41 of the CXA1802. Is there any chance that the two signals would be directly connected between the two chips?
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PC Engine Homebrew News: The duo that brought you FX-Unit Yuki returns! A demo for "Nyanja!" is available, an action platformer akin to games like Bubble Bobble & Snow Bros in gameplay style. |
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#2
Console Repair/Mod Center / Re: Dead CD Spindle Motor? How to Replace?
10/21/2022, 09:39 AM
So I wired in the new harness, plugged in all the cables, set the spindle to what appeared to be an appropriate height, popped in a regular CD drive, put the magnetic clamp on the CD and . . . the disc refused to spin. I swapped back the original assembly and same result, no spinning. I think the BA6290A may be on its last legs. While the drive sled motor works, that seems to be less of a power draw than the spindle motor. I can also see the laser move up and down to focus and through my camera see the laser light.
I should also mention that the HuCard portion of the console works perfectly and is RGB modded with the modern doujindance mod. When I try to run a CD I get the typical "Please Set Disc!" message.
I should also mention that the HuCard portion of the console works perfectly and is RGB modded with the modern doujindance mod. When I try to run a CD I get the typical "Please Set Disc!" message.
#3
Console Repair/Mod Center / Dead CD Spindle Motor? How to Replace?
10/20/2022, 08:53 PM
I have acquired a recapped PC Engine Duo, but when I got it the CD spindle did not spin up sufficiently to make the disk spin and nothing could be read. I could see the laser head moving up and down, so I thought that the motors may be bad. I bought a new disk laser assembly : https://www.ebay.com/itm/182710804499 to replace the old one.
When I got the new assembly today, I found two problems with it. First, the wiring was different but the same points are present. The second issue is much more of a problem. Simply put, the spindle platter on which the disc sits is below the laser head assembly. If you put a disc on the platter, half of the disc will rest on the laser assembly plastic. I don't know how this was supposed to work with anything, but I do notice that there is a silver shaft that has room to move the platter upward on this assembly whereas on the old assembly the shaft was about as high as it could get.
I really believe that the disc shaft motor on my old assembly is not working anymore. I applied ~3v to it and the spindle did not move where it did move on my new assembly. The disc spindle motor and drive sled motor are powered off the came cable and BA6290A, and the drive sled works fine. I found out how to adjust the height of the platter relative to the shaft, so I should know more once I replace the power cable from the assembly.
When I got the new assembly today, I found two problems with it. First, the wiring was different but the same points are present. The second issue is much more of a problem. Simply put, the spindle platter on which the disc sits is below the laser head assembly. If you put a disc on the platter, half of the disc will rest on the laser assembly plastic. I don't know how this was supposed to work with anything, but I do notice that there is a silver shaft that has room to move the platter upward on this assembly whereas on the old assembly the shaft was about as high as it could get.
I really believe that the disc shaft motor on my old assembly is not working anymore. I applied ~3v to it and the spindle did not move where it did move on my new assembly. The disc spindle motor and drive sled motor are powered off the came cable and BA6290A, and the drive sled works fine. I found out how to adjust the height of the platter relative to the shaft, so I should know more once I replace the power cable from the assembly.
#4
Console Repair/Mod Center / Re: PC Engine Duo Repair and Mod Advice
05/10/2015, 09:07 AM
Quote from: thesteve on 05/08/2015, 10:06 AMBypassing the choke worksSo, I should either desolder the ground pin or cut the trace to the ground pin on the DIN and use a patch wire to connect it to ground. Where is a good place to get the proper ground?
The issue with the chokes is your using a shared ground pin
#5
Console Repair/Mod Center / Re: PC Engine Duo Repair and Mod Advice
05/08/2015, 09:35 AM
Quote from: thesteve on 05/07/2015, 08:44 PMthe original duo runs all the sin=gnals through chokesIf the AV lines are run through a choke, would bypassing the choke fix the issue? How can that be done? By contrast to the composite video signal, the added RGB lines are not run through a choke, so would adding chokes to those lines balance out the issue and remove the jailbars?
the ground as well
this causes an inverted current pulse on the ground pin
#6
Console Repair/Mod Center / Re: PC Engine Duo Repair and Mod Advice
05/07/2015, 10:19 PM
I have read that a pair of tantalum 22uF capacitors on the 6260A may fix the issue. Is there any other possible fix, or is it just inherent to the chip itself and nothing can be done?
#7
Console Repair/Mod Center / PC Engine Duo Repair and Mod Advice
05/06/2015, 10:25 PM
A friend of mine let me borrow his PC Engine Duo he received from an ebay seller from Japan called doujindance. doujindance had replaced many of the surface mount capacitors and had installed an RGB mod. He replaced the 5-pin DIN AV port with an 8-pin DIN port for the RGB lines. There is a small board connected on one end to the DIN and on the other end to what I presume are the appropriate lines from the HuC6260A on the underside of the PCB. I also understand that the CD-ROM laser assembly has been replaced.
Issue One : Freezes when playing ADPCM from CD
When I received it, I was able to test the HuCard slot with a Turbo EverDrive, and that works just fine. However, I have been having serious problems with CD games crashing. At first, I was only using CD-R backups, typically with high quality Taiyo Yuden CD-Rs burnt at 16-24x. Many games would load correctly, but several would crash at certain identifiable points :
Ys Book I and II - Start a new game, game will freeze at the screen "In the Beginning"
Ys III - Game froze during the scene in beginning where Dogi speaks to the girl.
Ys IV - Game froze after Dogi speaks for the first time
Dracula X - Game freezes at loading FMV cutscenes.
All these instances have something in common, at these points the game will need to stream digitized ADPCM speech or sound effects from the CD. I understand that the chip responsible for streaming ADPCM is the M5205 OKI ADPCM Speech Integrated Circuit. At these points, I can reliably reproduce the crash. Trying to narrow down the causes, I tried a genuine Ys Book I and II CD and it crashed at the same point. These games will work if these areas are avoided (sometimes not possible) and CD audio will play fine. I tried fiddling with the laser adjustment pots to no avail.
There are other instances in some of these games where ADPCM is used and I never hear the speech or sound effect, but the game will not freeze. Once or twice, ADPCM did work and Dracula X and Ys Book I and II did not crash at these points or any other point and played all speech and sound effects back correctly. I could not figure out why the ADPCM would occasionally work but usually fail. I suspect that this chip is failing and needs replacement, console5 offers them for a reasonable price. Alternatively, I may need to replace the rest of the surface mount caps that have not been previously replaced. Any advice would be appreciated.
Issue Two : Jailbars in RGB Output
When I looked at the PC Engine's Duo's RGB output through a Framemeister, it generally looked great, but on some games, jailbars were quite noticeable. These jailbars are not present on the native composite video output. In this post, you can see pictures taken of my own screen :
http://nerdlypleasures.blogspot.com/2015/05/fun-with-framemeister.html
In the beginning Bonk's Adventure, they are very noticeable, with other games their visibility varies. It is something that once it has been seen, it just cannot be unseen.
Now the mod that doujindance installed looks to be using a tiny amplifier chip and some passive components. It does not bring composite sync to the AV connector, there just aren't enough pins on the connector. Sync comes from the composite video sync. Do I need a different mod or do I need to bring composite sync to the Framemeister?
Issue One : Freezes when playing ADPCM from CD
When I received it, I was able to test the HuCard slot with a Turbo EverDrive, and that works just fine. However, I have been having serious problems with CD games crashing. At first, I was only using CD-R backups, typically with high quality Taiyo Yuden CD-Rs burnt at 16-24x. Many games would load correctly, but several would crash at certain identifiable points :
Ys Book I and II - Start a new game, game will freeze at the screen "In the Beginning"
Ys III - Game froze during the scene in beginning where Dogi speaks to the girl.
Ys IV - Game froze after Dogi speaks for the first time
Dracula X - Game freezes at loading FMV cutscenes.
All these instances have something in common, at these points the game will need to stream digitized ADPCM speech or sound effects from the CD. I understand that the chip responsible for streaming ADPCM is the M5205 OKI ADPCM Speech Integrated Circuit. At these points, I can reliably reproduce the crash. Trying to narrow down the causes, I tried a genuine Ys Book I and II CD and it crashed at the same point. These games will work if these areas are avoided (sometimes not possible) and CD audio will play fine. I tried fiddling with the laser adjustment pots to no avail.
There are other instances in some of these games where ADPCM is used and I never hear the speech or sound effect, but the game will not freeze. Once or twice, ADPCM did work and Dracula X and Ys Book I and II did not crash at these points or any other point and played all speech and sound effects back correctly. I could not figure out why the ADPCM would occasionally work but usually fail. I suspect that this chip is failing and needs replacement, console5 offers them for a reasonable price. Alternatively, I may need to replace the rest of the surface mount caps that have not been previously replaced. Any advice would be appreciated.
Issue Two : Jailbars in RGB Output
When I looked at the PC Engine's Duo's RGB output through a Framemeister, it generally looked great, but on some games, jailbars were quite noticeable. These jailbars are not present on the native composite video output. In this post, you can see pictures taken of my own screen :
http://nerdlypleasures.blogspot.com/2015/05/fun-with-framemeister.html
In the beginning Bonk's Adventure, they are very noticeable, with other games their visibility varies. It is something that once it has been seen, it just cannot be unseen.
Now the mod that doujindance installed looks to be using a tiny amplifier chip and some passive components. It does not bring composite sync to the AV connector, there just aren't enough pins on the connector. Sync comes from the composite video sync. Do I need a different mod or do I need to bring composite sync to the Framemeister?
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