Differences

This shows you the differences between two versions of the page.

--- blog:x68_pro_fault [2020/08/06 21:27] – [Okay, lets replace ALL capacitors] john
+++ blog:x68_pro_fault [2021/02/24 14:03] (current) – [The Final Curtain] john
@@ Line 252: / Line 252: @@
 ----
-=== Capacitor List ===
-Following the visual check, I made a list of all the (electrolytic) capacitors on the boards:
-^ Number ^ Board ^ Capacitance ^ Voltage ^ Temperature Rating ^ Notes ^
-| C1	 | Main  |0.47uf |50v |85c | |
-| C5	 | Main  |220uf |6.3v |85c | |
-| C12	 | Main  |330uf |6.3v |85c | |
-| C13	 | Main  |100uf |16v |85c | |
-| C15	 | Main  |330uf |16v |85c | |
-| C16	 | Main  |470uf |6.3v |85c | |
-| C38	 | Main  |4.7uf |50v |85c | |
-| C39	 | Main  |4.7uf |50v |85c | |
-| C40	 | Main  |470uf |10v |85c | |
-| C41	 | Main  |470uf |10v |85c | |
-| C43	 | Main  |470uf |10v |85c | |
-| C44	 | Main  |3300uf |6.3v |85c |Large cap near rear IO panel|
-| C47	 | Main  |4.7uf |50v |85c | |
-| C48	 | Main  |4.7uf |50v |85c | |
-| C49	 | Main  |4.7uf |50v |85c | |
-| C50	 | Main  |100uf |10v |85c | |
-| C56	 | Main  |33uf  |10v |85c | |
-| C201	 | Sub   |100uf |6.3v |85c | |
-| C202	 | Sub   |100uf |10v |85c | |
-| C203	 | Sub   |100uf |10v |85c | |
-| C204	 | Sub   |330uf |6.3v |85c | |
-| C205	 | Sub   |47uf |16v |85c | |
-| C207   | Sub   |10uf |16v |85c | |
-| C210	 | Sub   |47uf |16v |85c | |
-| C211   | Sub   |100uf |6.3v|85c | |
-| C213	 | Sub   |4.7uf |50v |85c | |
-| C214	 | Sub   |47uf |16v |85c | |
-| C215	 | Sub   |47uf |16v |85c | |
-| C218	 | Sub   |100uf |6.3v |85c | |
-| C220	 | Sub   |4.7uf |50v |85c | |
-| C221	 | Sub   |4.7uf |50v |85c | |
-| C222	 | Sub   |47uf |16v |85c | |
-| C223	 | Sub   |330uf |6.3v |85c | |
-| C224	 | Sub   |100uf |16v |85c | |
-| C225	 | Sub   |100uf |6.3v |85c | |
-| C226	 | Sub   |100uf |16v |85c | |
-| c227	 | Sub   |0.47uf |50v |85c | |
-| C231	 | Sub   |0.47uf |50v |85c | |
-| C232	 | Sub   |1uf |50v |85c | |
-| C233	 | Sub   |0.47uf |50v |85c | |
-| C234	 | Sub   |100uf |10v |85c | |
-| C238	 | Sub   |0.47uf |50v |85c | |
-| C239	 | Sub   |0.47uf |50v |85c | |
-| C240	 | Sub   |330uf |6.3v |85c | |
-| C241	 | Sub   |100uf |16v |85c | Failed |
-| C242	 | Sub   |330uf |6.3v |85c | |
-| C243	 | Sub   |100uf |16v |85c | Failed |
-| C244	 | Sub   |330uf |16v |85c | |
-| C249   | Sub   |1uf |50v |85c | |
-| C251   | Sub   |22uf |16v |85c | |
-| C255	 | Sub   |4.7uf |50v |85c | |
-| C256	 | Sub   |47uf |16v |85c | |
-| C262	 | Sub   |330uf |16v |85c | |
-| R221	 | Sub   |47uf |16v |85c | Cant make the number out, but its next to R221.|
-Yes, that's right; there are more than **50** electrolytic capacitors on the motherboard.
-Quantities:
-   * **6x** 0.47uF, 50v
-   * **9x** 4.7uF, 50v
-   * **2x** 1uF, 50v
-   * **1x** 10uF, 16v
-   * **1x** 22uF, 16v
-   * **1x** 33uF, 10v
-   * **7x** 47uF, 16v
-   * **3x** 100uF, 6.3v
-   * **4x** 100uF, 10v
-   * **5x** 100uF, 16v
-   * **1x** 220uF, 6.3v
-   * **5x** 330uF, 6.3v
-   * **3x** 330uF, 16v
-   * **1x** 470uF, 6.3v
-   * **3x** 470uF, 10v
-   * **1x** 3300uF, 6.3v
-----
 === Next Steps ===
@@ Line 463: / Line 382: @@
 **[Update - August 3rd 2020]** - Since there seems to be ongoing issues with the system, the only thing that makes sense to do at this point is to replace **all** capacitors.
-For the full list of caps on the main board, refer to the [[blog:x68_pro_fault#Capacitor_List|table above]]
+For the full list of caps on the main board, refer to the my [[blog:x68000_pro_cap_list|X68000 Pro]] capacitor list page.
 ----
@@ Line 546: / Line 465: @@
 ----
-=== Main an Sub-Boards Reconnected ===
+=== Main and Sub-Boards Reconnected ===
-{{:blog:img20200806212605.jpg?700|}}
+{{:blog:img20200806212605.jpg?700|}} - Both boards fully re-capped and fitted back into case again
 ----
@@ Line 580: / Line 499: @@
 | C107   | Drive spindle board  | 0.47uF      | 50v        |       |
-Remember that you need twice as many as listed above to do //both// drives.
+Remember that you need twice as many as listed above to do //both// drives, so the actual part list is:
+   * **2x** 0.47uF, 50v
+   * **4x** 6.8uF, 50v
+   * **2x** 10uF, 25v
+   * **2x** 22uF, 10v
+   * **2x** 22uF, 16v
+   * **2x** 22uF, 25v
+   * **2x** 100uF, 10v
+{{:blog:img_1716.jpg?350|}} - Drive control board; C101, C107 replaced (make sure you bend or fit a low profile caps)
+----
+=== Logic IC Components ===
+Not sure whether any of these will need replacing, but here's a list of all the discrete logic components on the board (excluding things like the sound chips, cpu, ram, video controller, etc):
+   * [[blog:x68000_pro_ic_list|Sharp X68000 IC list]]
+===== Another Round of Testing =====
+=== Audio Circuit Repair Test ===
+Well the op-amp and amplifier IC replacement fixed the issue with no sound coming from the speaker unless you had your ear up against it:
+{{jPlayerPlaylist>blog:x68000_op-amp_repaired.mp3}}
+It's still not the greatest in the world, but it's fine for a tiny little 0.5w case speaker.
+----
+=== Keyboard ===
+Keyboard is still inactive.
+----
+=== Joystick Ports ===
+Tried an MSX compatible pad in both port 1 and port 2, it doesn't register in Motos. The game won't let you start.
+----
+=== Floppy Drives ===
+Floppy drive 0 still works fine. Floppy drive 1 still spits the disk back out as soon as you've inserted it.
+----
+=== Memory ===
+The onboard 1MB, the additional 1MB from the IOData module and the extra memory on the XSIMM10ss card all test fine in memtest68k.
+----
+=== Booting Human68k DOS ===
+A Human68k dos boot disk still brings up the //"It was not possible to start the system, please reboot"// message.
+----
+==== So What Now? ====
+I'm out of ideas with the system now. I think there is quite likely some damage to one or more of the IC's on the boards, but where to start with that, I've no idea. I don't have a scope and I don't have an electronics background.
+**[Update September 2020]** - So I bought a '__working__' X68000 Pro from Japan, planning to use most of the parts from it to make a fully working system... but upon arrival... well, [[blog:x68_pro_fault2|see for yourself]].
+The plan now is to remove as much of the obviously unaffected components from the new 'donor' system as possible - desoldering chips, if necessary - and transplant them in to my 'mostly working' system that I've spent all of this effort on.
+Stay tuned, I'll be posting more progress below.
+====== The Final Curtain ======
+**[Update 24/02/2021]**
+After spending months more trying to get the system working I only just managed to get it booting a Human68k floppy - despite desoldering the last remaining surface mount chips from the IO sub board. Keyboard still didn't work, joystick still didn't work - making it completely unusable.
+Tracing signals and low level logic debugging is not what I want to get in to, so it's time to draw a line under all of this and move on. Perhaps someone more adept than myself could get this running again. But that's it for me; I need to move on.
+It's pretty sad to say that //were it not for the incorrect PSU wiring diagram//, this would have been an easy job and I'd have had months of fun playing with the system by now.