Title: Replacing VLSI chips to solve nonbooting cubes
Post by: barcher174 on May 02, 2016, 12:33:18 AM
Post by: barcher174 on May 02, 2016, 12:33:18 AM
All,
Do you have a cube that won't boot? Does it boot to a black screen, but the screen is still lit? The diagnostic LED will also not be lit or may blink undocumented codes.
1) Check the CPU and ROM
2) Check the RTC chip and associated diodes
3) Replace the ICP (integrated channel processor - The VLSI next to the CPU)
Does the cube not provide video at all?
It could be the video IC
Where to get these parts? A first generation nextstation has an identical ICP and video chip. A typical failure for a video IC is detached chip legs. I have not seen a case of apparent physical damage to the ICP. I think thermal stress is killing the video IC. I received the board pictured above with both chips removed. Rob believed it came from Bell Services, which gave me the idea that these were common failures at the time. I have now revived 2 additional cube boards using this technique.
--
Brian
Do you have a cube that won't boot? Does it boot to a black screen, but the screen is still lit? The diagnostic LED will also not be lit or may blink undocumented codes.
1) Check the CPU and ROM
2) Check the RTC chip and associated diodes
3) Replace the ICP (integrated channel processor - The VLSI next to the CPU)
Does the cube not provide video at all?
It could be the video IC
Where to get these parts? A first generation nextstation has an identical ICP and video chip. A typical failure for a video IC is detached chip legs. I have not seen a case of apparent physical damage to the ICP. I think thermal stress is killing the video IC. I received the board pictured above with both chips removed. Rob believed it came from Bell Services, which gave me the idea that these were common failures at the time. I have now revived 2 additional cube boards using this technique.
--
Brian
Title: Re: Replacing VLSI chips to solve nonbooting cubes
Post by: Rob Blessin Black Hole on May 02, 2016, 02:25:55 AM
Post by: Rob Blessin Black Hole on May 02, 2016, 02:25:55 AM
Quote from: "barcher174"All,. Hello Brian : Excellent work ,I'm always very impressed ! Best regards Rob Blessin
Do you have a cube that won't boot? Does it boot to a black screen, but the screen is still lit? The diagnostic LED will also not be lit or may blink undocumented codes.
1) Check the CPU and ROM
2) Check the RTC chip and associated diodes
3) Replace the ICP (integrated channel processor - The VLSI next to the CPU)
Does the cube not provide video at all?
It could be the video IC
Where to get these parts? A first generation nextstation has an identical ICP and video chip. A typical failure for a video IC is detached chip legs. I have not seen a case of apparent physical damage to the ICP. I think thermal stress is killing the video IC. I received the board pictured above with both chips removed. Rob believed it came from Bell Services, which gave me the idea that these were common failures at the time. I have now revived 2 additional cube boards using this technique.
--
Brian