Sorry, this entry is only available in Italian.

Autopsy:

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This computer/console in good cosmetic condition is arrived for a repair from a friend a few weeks ago. The defect is The Black Screen of Death, the computer turns on but doesn’t turn off, the standby LED remains faint green.

Unfortunately after several hours spent to trying the fault and i have tried just everything, the computer is still dead, my suspicion falls on the Custom Chip “SCOTCH” IX 1267CE from Sharp.

Components that have been tested and replaced:

• Tested all capacitors.
• Tested all transistors.
• Tested all SMD fuses.
• Test all the Coils.
• Tested all voltages.
• Replaced 74LS08 ic that controls the logic of power on/standby.
• Replaced 74LS244 ic that controls the logic of power on/standby.
• Replaced the power supply.

Download: Sharp X68000 Schematics (1625)

from Wikipedia:

The Sharp X68000, often referred to as the X68k, is a home computer released only in Japan by the Sharp Corporation. The first model was released in 1987, with a 10 MHz Motorola 68000 CPU (hence the name), 1 MB of RAM and no hard drive; the last model was released in 1993 with a 25 MHz Motorola 68030 CPU, 4 MB of RAM and optional 80 MB SCSI hard drive. RAM in these systems is expandable to 12 MB, though most games and applications did not require more than two.

The X68k ran an operating system developed for Sharp by Hudson Soft, called Human68k, which features commands very similar to those in MS-DOS (typed in English). Pre-2.0 versions of the OS had command line output only for common utilities like “format” and “switch”, while later versions included forms-based versions of these utilities, greatly improving their usability. At least three major versions of the OS were released, with several updates in between. Other operating systems available include NetBSD for X68030 and OS-9.

Early models had a GUI called “VS” (Visual Shell); later ones were packaged with SX-WINDOW. A third GUI called Ko-Windows existed; its interface is similar to Motif. These GUI shells could be booted from floppy disk or the system’s hard drive. Most games also booted and ran from floppy disk; some were hard disk installable and others require hard disk installation.

Since the system’s release, Human68k, console, and SX-Window C compiler suites and BIOS ROMs have been released as public domain and are freely available for download.

Early machines use the rare Shugart Associates System Interface (SASI) for the hard disk interface; later versions adopted the industry-standard small computer system interface (SCSI). Per the hardware’s capability, formatted SASI drives can be 10, 20 or 30 MB in size and can be logically partitioned as well. Floppy disks came in a couple of different formats, none of which are natively readable on other platforms, although software exists that can read and write these disks on a DOS or Windows 98 PC.

source: wikipedia

I have received these computers to be repaired for a friend.

Defects found on the Commodore VIC-20:

• Error message (device not present) when trying to access the IEC devices, like a Floppy Drive.

Defects found on the Commodore 64:

• Black screen of death after installing the missing roms.

The repair of the Commodore VIC-20 was made by replacing a HEX Inverter Buffer 7406.

The repair of the Commodore C64 was made by replacing the MOS 906114-01 (PLA – Programmable Logic Array).

Gallery of repairs:

This is the official demo party results from Stary Piernik 8 (Top 3 Entries only). See also the CSDB Stary Piernik 8 section for more informations and download.

C64 Demo:

• Fogyish
• In Thorn by Sabath
• Kazachski piesek by Provocator

C64 Music:

• Nasty Bitch by Wacek
• One Life by Surgeon
• Filth And Scottish Words 50% by Randall

C64 Graphics:

• The Jungle by JSL
• Black Sun Logo by Miras
• Gdzie by Maciaszczyk

Download: Stary Piernik 8 full Party stuff (1064)

source: noname.c64.org/csdb/

Thanks go to: Damiano (manosoft) and my Brother Alessandro.

Things that have been donated:

• 4 x Box of Verbatim Datalife 3.5  2HD Floppy Disk.
• 1 x Apple Keyboard for my iMac G3 “Bondi Blue” M5521
• 1 x Iomega Zip Drive SCSI + Cable.
• 1 x Iomega Zip Drive USB + Cable.
• 11 x Zip Disk.
• Some 3.5 Floppy Disk.

Autopsy:

Finally i have replaced my old and inaccurate Capacitor tester with a better one. My lab is beginning to have a semblance semi professional ;-D

Download: Peak Atlas ESR+ 70 User Guide (1383)

Video Review:

Mentor Colour 6 (Pong clone) has been Repaired

Defects:

• Black screen of death.
• No sound.

The problem of the power supply has been fixed by replacing the transitor CS 9013 that is used in a very bizarre way to lower the voltage from 9v to 6.85v. The problem of the audio was always caused by a transistor CS 9013 brutally in short circuit. In this case, the transistor is used like a amplifier.

The transistor CS 9013 can be replaced with a BC 337 that it’s equivalent.

I thank a friend for the donation.

Donated item:

• Sandy Sinclair QL  Printer Converter.
  • The Sandy Printer Converter was a serial to parallel printer interface made by Sandy (UK).

The HxC Floppy Drive Emulator is a software and hardware system created by jfdn aka Jeff.

The aim of this project is to replace the floppy disk drive by an electronic device emulating the floppy disk drive (list of supported Computer/Hardware).

There are two differents emulators:

• A USB version which allows to connect the floppy disk drive interface of the computer to a PC via a USB cable.
• A SDCARD version which allows to emulate floppy disks which images are stored in a SDCARD.

Changelog SD HxCFloppyEmulator v1.8.2.40 (fat) & v2.1.2.40 (slim):

• Index signal behavior corrected while the host system attempt to format a drive without image loaded.

Download:

• HxC Floppy Emulator Firmware v1.8.2.40 (1037)
• Slim HxC Floppy Emulator Firmware v2.1.2.40 (1068)

source: hxc2001.free.fr

This gallery shows some stages of the cleaning and repairing the Commodore CBM 610.

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Defects found on the Commodore CBM 610:

• Black Screen of Death.
• Garbage characters on the screen.
• Keyboard Yellowed.
• Filter capacitor exploded.

The black screen of death was fixed by replacing the CPU MOS 6509A and the problem of garbage characters on the screen was fixed by replacing the ROM characters with a EPROM 2532 suitably programmed.

The yellowed keyboard was replaced with a new one in good condition of the Commodore CBM 710. I like Commodore. What will be the difference of a CBM 710 and a CBM 610 keyboard? nothing, are the same! no! on the keyboard of the CBM 710 has two wires reversed! (brown/red) ;-D

The filter capacitor exploded has been removed.

This gallery shows some stages of the repairing of the two Floppy Drives Commodore SFD-1001.

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Defects found on the two Floppy Drives:

• Both floppy drives had the capacitors that leaked acid on the motor control pcb.
• Both floppy drives had the closing arm cracked.

The difficulty was rebuild the tracks of the pcb and remove the most of the leaked acid of the capacitors. Unfortunately on the aesthetic level this type of repair are not perfect, but i’m glad that now work.

To test the correct operation of the Floppy Drives i have used a Commodore CBM (PET) 2001, and a Commodore CBM 610.

Hoxs64 written by David Horrocks is a Commodore 64 emulator for Microsoft Windows 2K/XP/Vista/Seven (DirectX 9+)

The emulator substantially reproduces this legacy machine in minute detail.

Changelog:

• Fixed an EasyFlash cartridge fault when loading a 4KB banked CRT file or state file.

Download:

• Hoxs64 64 bit v1.0.8.6 (934)
• Hoxs64 32 bit v1.0.8.6 (968)
• Hoxs64 Ansi Win98/2K v1.0.8.6 (951)

source: hoxs64.net

Hoxs64 written by David Horrocks is a Commodore 64 emulator for Microsoft Windows 2K/XP/Vista/Seven (DirectX 9+)

The emulator substantially reproduces this legacy machine in minute detail.

Changelog:

• Added emulation state file save, load and restore facility.
• Added Epyx Fastload cartridge.
• Added screen border hide options.
• Fixed Retro Reply cartridge banking fault.
• Reworked the CPU code to accommodate XAA/ANE for a MOS8500 as reported by Visual6502.org

Download:

• Hoxs64 64 bit v1.0.8.5 (1259)
• Hoxs64 32 bit v1.0.8.5 (1238)
• Hoxs64 Ansi Win98/2K v1.0.8.5 (1296)

source: hoxs64.net

Attitude is a disk magazine for the Commodore 64 computer by Triad. We hope you enjoy this issue as much as you did the previous ones!

Download: Attitude Diskmagazine #14 (1179)

source: noname.c64.org

Autopsy:

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I have received this computer to be repaired for a friend with a classic startup fault; the Black screen of Death.

After careful analysis of the problem and thanks to Alessandro Polito for the test, the failed component was the CPU 6509.

from Wikipedia:

The Commodore CBM-II series was a short-lived range of 8-bit personal computers from Commodore Business Machines (CBM), released in 1982 and intended as a follow-on to the Commodore PET series.

The CBM-II had two incarnations, the P series (P = personal, or, home use) and the B series (B = business use). The B series was available with a built-in monochrome monitor (hi-profile) with detached keyboard, and also as a single unit with built-in keyboard but no monitor (lo-profile). These machines were known as the “Porsche PETs” for their unique styling.

The P series used the VIC-II 40-column color video chip like the C64. It also included two standard Atari-style joystick ports. The 6509 CPU ran at 1 MHz in the P series due to the use of the VIC-II chip.

The B series used a 6545 CRTC video chip to give an 80-column “green screen” monochrome output more suitable for word processing and other business use than the VIC-II’s 40-column display. Most models have the Motorola 68B45 installed which is a pin compatible variant rather than the MOS 6545A1 2 MHz part. On the B series the 6509 CPU ran at 2 MHz.

Features common to both the P and B series included an MOS Technology 6509 CPU, an enhanced version of the venerable 6502, that was capable of addressing up to 1 megabyte of RAM via bank switching (however, no CBM-II model came with more than 256 kilobytes of RAM, 1/4 megabyte). The sound chip was the 6581 SID, the same one that was used in the popular Commodore 64 (C64) but with some limitations as it was over-clocked to 2 MHz. Additionally, the CBM-II had an industry-standard RS-232 serial interface and an IEEE-488 parallel bus (for use by disk drives and printers) just like the PET/CBM series. The CBM-II’s built-in operating system used an enhanced version of CBM BASIC version 4.0.

An optional Intel 8088-based coprocessor board allowed the CBM-II series to run CP/M-86 1.1 and MS-DOS 1.25; however, the computers were not IBM PC compatible and very little, if any, software taking advantage of this capability ever appeared. The coprocessor board only ran on hi-profile machines due to power supply and mechanical spacing requirements.

The production naming within the United States and Canada was the B128/B256 and CBM128-80/CBM 256-80 while in Europe they were known as the 600 and 700 series respectively (no “B” in front of the model number). The P machine was known worldwide as the 500 series. There are prototype models though such as the B500 (earlier B128 design) and B700 (earlier CBM 128-80/CBM 256-80 design) known to exist.

Due to the popularity of the C64, the P series was cancelled in the United States before it could be officially released; however, a few dealers who received preproduction units sold them. As these computers had not received approval from the Federal Communications Commission, this caused legal problems for Commodore. The units were recalled and destroyed, but a very small number exist today, in private collections. At least one model, the P500, was commercially released in Europe but only sold in small numbers.

source: wikipedia