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--- blog:bbc_riscpc_fix [2020/07/26 12:43] – [Acorn Risc PC 700 Refurb] john
+++ blog:bbc_riscpc_fix [2020/07/28 20:05] (current) – john
@@ Line 21: / Line 21: @@
 Oh dear. That will be one completely failed battery cell. With nasty battery gunk coming out.
-===== Removing The Battery =====
+==== Removing The Battery ====
 First job is to remove the power supply, to get access to remove the battery and get a closer look at the board... it's held in with one screw, into a screw post in the case...
@@ Line 41: / Line 41: @@
 Next task is to try powering it on again with just the basic peripherals connected.
-===== Risc PC Board =====
+==== Risc PC Board ====
 The mainboard itself looks okay, no signs of any other corrosion or similar.
@@ Line 47: / Line 47: @@
 {{:blog:img_1535.jpg?400|}}
-===== PC Second Processor Card =====
+==== PC Second Processor Card ====
 Unfortunately it looks like this one hasn't aged too well either; on removal of the card from the processor slot, one of the surface mount capacitors literally dropped off the card. It looks like it has been hanging on purely by the residue of the cap itself. Urgh.
@@ Line 57: / Line 57: @@
 This one is going to need a clean up and a replacement surface mount cap fitting. Oh what fun! :(
-===== StrongARM Processor Card =====
+==== StrongARM Processor Card ====
 The StrongARM card looks fine:
@@ Line 63: / Line 63: @@
 {{:blog:img_1540.jpg?400|}}
-===== ANT Ethernet Module =====
+==== ANT Ethernet Module ====
 The ethernet module is by ANT, and comes with a ROM labelled as 'Access / AUN / TCPIP'... which of these it has enabled (back when Acorn networking modules were sold, you had to pay for the additional features).
@@ Line 71: / Line 71: @@
 I won't know what is enabled on it until I can get the system up and running again. Again, no visible damage from the battery leak.
-===== 72pin SIMM Modules =====
+==== 72pin SIMM Modules ====
-Two sticks of what appear to be 32MB SIMMS were fitted to the machine.
+Two sticks of what appear to be a 8MB and 32MB SIMM were fitted to the machine.
 The first one is an unusual one in that it has sockets for additional DRAM chips to be fitted - I guess it meant the manufacturer only had to produce one board design:
@@ Line 83: / Line 83: @@
 {{:blog:img_1545.jpg?400|}}
-===== VRAM Module =====
+==== VRAM Module ====
 The Risc PC was the first design from Acorn to have dedicated video memory; all other models sharing video RAM with main memory. You could have 0MB, 1MB or 2MB module installed. This Risc PC 700 has the extra fancy 2MB module which allows higher resolutions and colour depths:
@@ Line 91: / Line 91: @@
 Again, no visible damage from the battery leak.
-===== Backplane Module =====
+==== Backplane Module ====
 This is the riser that allows add-in cards to be fitted.
@@ Line 99: / Line 99: @@
 No damage seen.
-===== A/D Add-in Card =====
+==== A/D Add-in Card ====
 Not sure of the original purpose of this card, but it was fitted and appears to have no damage from the battery leak:
 {{:blog:img_1548.jpg?400|}}
+===== Re-Testing After Battery Removal =====
+I reassembled a minimal system:
+    * Power supply
+    * Main board
+    * StrongARM processor
+    * 8MB SIMM
+    * VRAM SIMM
+{{:blog:img_1552.jpg?400|}}
+Pressed the power button holding 'Del' (CMOS reset routine for the Acorn) and crossed my fingers:
+{{:blog:img_1549.jpg?400|}}
+Hurrah!
+At this point it wouldn't boot to the desktop, so I tried hooking up the disc drive and gave it a reset:
+{{:blog:img_1550.jpg?400|}}
+Even better! There seems to a working OS install on the drive as I saw various messages about plugins and toolboxes being loaded from the drive. Sadly it didn't give me a fully working desktop as it eventually threw this error in my face:
+{{:blog:img_1551.jpg?400|}}
+To be honest I'm not surprised an old 800MB IDE drive from-gods-know-when has a few errors. The plan would be to swap it out (or, preferably, leave it installed but unplugged) with a compact flash card reader instead.
+===== Case cleaning! =====
+Just a bit of soap and water and a magic eraser block:
+{{:blog:img20200726184832.jpg?400|}} {{:blog:img20200726184955.jpg?400|}}
+===== Restoring Risc OS =====
+It's been a long time since I've done it, so this is also for my own peace of mind.
+=== Steps to reinstall Risc OS to hard drive ===
+   * Unzip the {{ :blog:splug226.zip|!SparkPlug}} zip file, and copy the self-extracting .bas file to a DOS floppy
+   * Run SparkPlug from RAM
+   * Copy {{ :blog:hform248.zip |!HForm.zip}} to a DOS floppy
+   * Unpack !HForm to RAM
+   * Format your new drive, make it bootable
+   * Copy !SparkPlug to the formatted hard drive
+   * Copy {{ :blog:split.zip|!Split.zip}} to a DOS floppy
+   * Unpack !Split.zip and copy to your formatted hard drive
+   * Use the MS-DOS {{ :blog:split_stubsg.zip|SPLIT.EXE}} on the PC side (included in addition to versions for other platforms) to split the Risc OS 3.7 {{ :blog:uniboot.zip|universal boot sequence}} into two 1.4MB images ({{ :blog:uniboot_splits.zip|pre-split version}})
+   * Copy each image on a single DOS floppy to the Risc PC
+   * Re-join the two split files using !Split and drag the unzipped !Boot sequence to your hard drive
+{{:blog:img_1554.jpg?400|}} {{:blog:img_1556.jpg?400|}}
+All working, but for some reason at 1024x768 either my OSSC or monitor cuts off a good chunk of the left hand side of the screen:
+{{:blog:img_1557.jpg?400|}}
+... one more thing to look at!
+===== Networking =====
+To do!