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CBS ColecoVision: diagnosing and fixing motherboard faults

July 26th, 2013 No comments

I have decided to repair my Coleco Vision Secam version (RGB) purchased some years ago in a full working state, today is died. Below a description of the defect and of components being replaced.

Defect: dirty sprite

  • 3 x 4116 (RAM)

MicroBee PC 85 (Model II) Keyboard Repair

July 24th, 2013 No comments

I have received this computer in excellent cosmetic condition but unfortunately with some dead keys of the keyboard.

The trick of the repair is cleaning the two little strips and the small conductive button (see the photos)

Applied Technology MicroBee PC 85 (Model II) + ROM Eprom Dump

July 24th, 2013 No comments
Applied Technology MicroBee PC 85 (Model II)

Autopsy:

from Wikipedia:

MicroBee (Micro Bee) was a series of home computers by Applied Technology, later known as MicroBee Systems.

The original MicroBee computer was designed in Australia by a team including Owen Hill and Matthew Starr. It was based on features available on the DG-Z80 and DG-640 S-100 cards developed by David Griffiths, TCT-PCG S-100 card developed by TCT Micro Design and MW6545 S-100 card developed by Dr John Wilmshurst. It was originally packaged as a two board unit, with the lower “main board” containing the keyboard, Zilog Z80 microprocessor, Synertek 6545 CRT controller, 2 kB of “screen” RAM, 2 kB of character ROM (128 characters) and 2 kB of Programmable Character Graphics (PCG) RAM (128 characters). Each byte in the screen RAM addressed a character in either the character ROM or PCG RAM. A second board, termed the “core board”, contained the memory, and on later models also included a floppy disk controller.

The computer was conceived as a kit, with assembly instructions included in Your Computer magazine, in June 1982. After a successful bid for the New South Wales Department of Education computer tender, the computer was repackaged in a two-tone beige and black case, and sold pre-built. The 16 kB ROM held the MicroWorld BASIC interpreter written by Matthew Starr and DGOS (David Griffiths Operating System) compatible System Monitor. In addition to the 16 kB ROM, there is additional ROM socket for optional programs such as WORDBEE (Word processor) or EDASM (a Z80 Editor/Assembler that was written by Ron Harris).

Original MicroBees ran at a clock speed of 2 MHz, with a video dot clock of 12 MHz, which was sufficient to display 64 × 16 characters (512 × 256 pixels) on a modified television or composite monitor. The original machines were supplied with 16 or 32 kB of static RAM, and stored programs on cassette, using 1200 Baud encoding.

Download: MicroBee PC 85 ROM Eprom Dump (1495)

source: wikipedia

Nordlicht 2013: Official demo party results

July 22nd, 2013 No comments

This is the official demo party results from Nordlicht 2013 (Top 3 Entries only). See also the Nordlicht 2013 homepage for more informations.

Mixed:

  • Pimmelsafari by Metalvotze (Game)
  • Return of the Jedi (Game)
  • Hubbard Selector by Peiselulli (Music Collection)

Mixed Graphics:

  • Night Walk by Arsenic, Oxyron
  • Mind Collapse by Tristar & Red Sector Incorporated
  • Never Trust a c64 by Rabenauge

Mixed Music:

  • Lauter by dEViLOCk
  • N0rdl1cht 2013 by fieserWolf
  • Two Reds For One Blues by Mayday!

Mixed Demo:

  • Natura Morta by Tristar & Red Sector Incorporated
  • Zeropage Gravity by Tristar & Red Sector Incorporated
  • Call of the Past by Arsenic

Productions released outside compos:

  • D71 Ultimate V0.2 (Tool)
  • Demo of the Year 2013 by Phantasy/Hitmen/Laxity/Alpha Flight/Fossil/Oxyron/Chorus/Camelot/Censor Design (Demo)

Download: Nordlicht 2013 full Party stuff (1036)

source: noname.c64.org/csdb nordlicht.demoparty.info

Timex Computer 2048 (TC 2048) – Spectrum 48k Clone

July 21st, 2013 No comments
Timex Computer 2048 (TC 2048) - Spectrum 48k Clone

Autopsy:

from Wikipedia:

The TC 2048 or Timex Computer 2048 is a computer created by “Timex of Portugal, Lda”, a branch of Timex Corporation. It was highly compatible with the Sinclair ZX Spectrum computer, although differences in the ROM prevented 100% compatibility.

Timex Portugal sold the TC 2048 in Portugal and Poland, where it was very successful. Also, a NTSC version was sold in Chile. This computer forms the basis of an improved Spectrum-compatible machine, the Spectrum SE.

Timex Sinclair was a joint venture between the British company Sinclair Research and Timex Corporation in an effort to gain an entry into the rapidly growing early-1980s home computer market in North America. The choice of partnership was natural as Timex was already the main contractor for manufacture of Sinclair’s ZX81 and ZX Spectrum computers at its Scottish plant in Dundee.

It was Timex of Portugal, though, that took on the R&D and the local manufacturing of the models to be exported to the U.S. Although both Timex of Scotland and Timex of Portugal were full subsidiaries of Timex, internal rivalry, whether unintended or purported, meant there were no contacts nor experiences shared between the two plants. Timex of Portugal also sold the Timex Sinclair models in Portugal and Poland under the Timex Computer brand.

Technical specifications:

  • CPU: Zilog Z80A @ 3.50 MHz
  • ROM: 16 KB
  • RAM: 48 KB
  • Sound: Beeper (1 channel, 10 octaves and 10+ semitones via internal speaker)
  • Display:
    • Improved ULA offering additional screen modes:
    • Text: 32×24 characters (8×8 pixels, rendered in graphics mode)
    • Graphics: 256×192 pixels, 15 colours (two simultaneous colours – “attributes” – per 8×8 pixels, causing attribute clash)
    • Extended Color: 256×192 pixels, 15 colors with colour resolution of 32×192 (two simultaneous colours – “attributes” – per 1×8 pixels)
    • Dual Screen: (two 256×192 pixels screens can be placed in memory)
    • A monochrome 512×192 mode
  • I/O:
    • Z80 bus in/out
    • Tape audio in/out for external cassette tape storage
    • RF television out
    • Composite video monitor out
    • Kempston Joystick input

Download: Timex Computer 2048 Schematic (1505)

source: wikipedia

New CBS Coleco Vision cartridges for my collection

July 21st, 2013 No comments

New CBS Coleco Vision cartridges for my collection CBS Coleco Vision cartridges

New CBS Coleco Vision cartridges for my collection.

List of cartridges:

  • Antarctic Adventure by ©1984 Konami
  • BC’s Quest for Tires by ©1983 Sierra On-Line
  • Donkey Kong Junior by ©1982 Nintendo (France Secam Version)
  • Miner 2049er by ©1982 Micro Fun/Microlab inc.
  • Omega Race by ©1981 Bally Midway
  • Pitfall by ©1983 Activision
  • Q*Bert by ©1983 Parker Brothers
  • Roc’n'Rope by ©1984 Konami
  • Schtroumpfs by ©1983 Logiciel (France Secam Version)
  • Super Action Football by ©1984 CBS Toys
  • Tarzan by ©1984 Edgar Rice Burroughs Inc.
  • Tournament Tennis by ©1984 Imagic
  • Venture by ©1983 Exidy (France Secam Version)
  • Pitstop by ©1983 Epyx
  • Looping by ©1982 Venture Line Inc. (France Secam Version)
  • Subroc by ©1982 Sega
  • Turbo by ©1981 Sega (France Secam Version)
  • Cosmic Avenger by ©1983 Universal (France Secam Version)
  • Gorf by ©1981 Bally Midway (France Secam Version)
  • Zaxxon by ©1982 Sega (France Secam Version)

Some spare parts from a Friend

July 21st, 2013 No comments

I have received from a friend a couple of components that can be used as spare parts for the repairs. Thanks Andrea.

Close-up description:

  • 1 x Commodore CBM 4040 Dual Floppy Disk Drive PCB
  • 1 x Commodore CBM 8050/8250 Dual Floppy Disk Drive PCB
  • 2 x Texas Instruments TI-99/4A PCB
  • 1 x Main powersupply of Commodore CBM 4040/8050/8250 Dual Floppy Disk Drive.
  • 1 x Sinclair ZX Spectrum+
  • 1 x Sony HB-10P MSX

Philips Videopac G7000 (PAL) RGB Video Mod

July 20th, 2013 7 comments
Philips Videopac G7000 with RGB Output

Details:

I have found this RGB mod for the Philips Videopac G7000 console fom the gamesx site and i have decided to build the circuit to see if it works.

This mod is not easy to do, especially if one has no experience in electronics, however the result at the end is spectacular.

RGB DAC Schematics (click to zoom):

Download: Philips VideoPac G7000 Schematics (1879)

source: gamesx.com

HxC Floppy Emulator: Software v2.0.15.1

July 17th, 2013 No comments

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.

Release notes for the HxCFloppyEmulator software v2.0.15.1:

  • FAT12 Loader/generator : Default file creation date set to 1985 to avoid issue with non year 2000 compatibles machines (Kawasaki JS30 robots…).
  • Apple 2 Sectors generator : End of sector sync corrected, 6&2 GCR encoder corrected.
  • Track viewer : Sectors on track boundary display issue corrected.

Download:

source: hxc2001.free.fr lotharek.pl

HxC Floppy Emulator: Software v2.0.15.0 & DOS Disk Image Browser

July 15th, 2013 3 comments

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.

HxC Floppy Emulator DOS Disk Image Browser:

The HxC Floppy Emulator DOS Disk Image Browser is a simplified version of the HxC Floppy Emulator software. This version is designed to replace the VFD solution.

Avantages over the VFD solution:

  • No driver installation needed.
  • Support of 3 mode DOS floppy disk image (1KB sector size) (For PC98 based CNC machines).
  • Support of special/custom DOS floppy disk image (2.5MB,4.5MB,6.78MB…)
  • Ready to be used on non-windows systems (Mac, Linux,…) ! ;)
  • Simple use !

Release notes for the HxCFloppyEmulator software v2.0.15.0:

  • New Loader: SpeccyDos *.SDD support added
  • New Loader: Apple 2 DOS 3.3 (*.DO) & ProDOS (*.PO) raw file image added.
  • New Writer: HFE file with the HDDD A2 support for Apple II (http://www.bootzero.com/HDDD_A2_v1.2/HDDD_A2v1.2.html)
  • New Writer: Atari ST MSA file.
  • New Writer: TRS 80 *.JV3 file. (Done by David Barr ! Thanks to him :) )
  • New Writer: TRS 80 *.DMK file.
  • New Writer: PC88 *.D88 file.
  • FAT12 Loader/generator: Atari ST 902KB  format corrected.
  • FAT12 Loader/generator: Atari ST 4.23MB format corrected.
  • HFE File Writer: Track padding function corrected.
  • EDE File Loader: edt & edv file support added, ASR 10 gap3 adjusted to 36.
  • JV3 File Loader: Sector interleaving correctly implemented.
  • IMD File Writer: No allocated sector issue corrected.
  • XDMS Lib: UTF8 path support added.
  • LIBSAP Lib: UTF8 path support added.
  • New Track/Sector support: GCR “6 and 2″ Apple II DOS 3.3/ProDos.
  • FAT12 Disk Browser:  Handle freeing corrected
  • GUI – Drag & Drop Support: URI type path support added (Linux).
  • GUI – Track viewer window: New buttons to enable/disable track format analysis.
  • GUI – Log window: New buttons to enable/disable logs messages.
  • Raw Loader – Predefined raw formats added:
    • Roland W30/S330/W50/S50/S550 DD Floppy Disk.
    • OS9 1280KB Floppy Disk.
    • Linn/Forat 9000 Floppy Disk.
    • KORG T3 3″5 HD Floppy Disk.
    • Atari ST 3″5 DD Floppy Disk
    • Standard 3″5 DOS ED Floppy Disk
    • Special 2.5MB DOS EXHD Floppy Disk
    • Special 4.5MB DOS EXHD Floppy Disk.
    • Special 6.78MB DOS EXHD Floppy Disk.
  • Updated:
    • Ensoniq EPS 3″5 HD Floppy Disk : Gap3 adjusted.
    • Standard 3″5 DOS HD Floppy Disk : Gap3 adjusted.
    • Standard 3″5 DOS DD Floppy Disk : Gap3 adjusted.

Download:

source: hxc2001.free.fr lotharek.pl

Commodore CBM 8050 Cleaning and Repair

July 14th, 2013 1 comment

This gallery shows some stages of cleaning the Commodore CBM 8050 Dual Drive Floppy Disk. Below the defects and replacement parts.

Defect:

  • Died – Status LED: RED (5 Flash) Zero page error.

Replacement parts:

  • 1 x 6502
  • 1 x 6532
  • 1 x 6522
  • The connectors of write enable sensors are inserted incorrectly.
  • Missing +5v on the PCB of the sensor circuit.
  • Dirtiness in the write enable sensor drive 0
  • Cleaning floppy drive heads.
  • Cleaning belt of the floppy drive.
  • Removing the filter capacitor.
  • The Analog PCB of the Floppy Drive is not fixed properly.
  • The Locking screws of the external box are not original.
  • Lost the felt which push the Floppy Disk vs the head.
  • Disk is present (Switch Motor) dirty.
  • General Cleaning.

Test formatting floppy disk:

Commodore CBM 8050 Dual Drive Floppy Disk

July 14th, 2013 No comments
Commodore CBM 8050 Dual Drive Floppy Disk

Autopsy:

from Wikipedia:

The Commodore 8050 and Commodore 8250 were dual unit 5¼” floppy disk drives for Commodore International computers. They used a wide rectangular steel case form similar to that of the Commodore 4040, and used the IEEE-488 interface common to Commodore PET/CBM computers.

The 8050 was a single sided drive, whereas the 8250 could use both sides of a disk simultaneously. Both used a “quad” density format storing approximately 0.5 megabyte per side. The density of media was similar to later PC high density floppy disks, but the 8050 and 8250 could not use PC high density disks reliably. Since “quad” density disks were rare even at the time, users quickly found that typical double density floppy disks had enough magnetic media density to work in these drives.

These drives were not dual mode, so they could not read or write disks formatted by the more common lower capacity Commodore 1541 or Commodore 4040 models. Some variants of these drives existed. The Commodore 8250LP was the 8250 in a lower profile, tan-colored case. The Commodore SFD-1001 was a single drive version of the 8250 in a Commodore 1541 style case (similarly to the Commodore 2031LP), often used by bulletin board systems for their physical similarity to 1541s and high capacity and speed.

source: wikipedia

CBM prg Studio v2.7.0 released

July 13th, 2013 No comments

CBM prg Studio Version 2.7.0 is released. There are a lot of new features in this version. I’d really appreciate it if you report any bugs you find or have any suggestions/comments.

CBM prg Studio allows you to type a BASIC or Machine Code program in using a nice Windows environment and convert it to a ‘.prg’ file which you can run on an emulator, or even a real C64 / VIC20 or PET if you’re feeling brave and have the right kit.

CBM prg Studio is the result of merging C64PrgGen and VIC20PrgGen. Adding new features and fixing bugs in two apps which were 95% similar was a bit of a nightmare so merging them made sense.

It was also a good opportunity for a face lift and to add some new features, such as:

  • Programs are project based, meaning all related source files, sprite files etc. are kept in one place and multiple source files can be linked more easily.
  • Tabbed MDI.
  • Syntax highlighting.

What CBM prg Studio isn’t is a front-end for tok64, cbmcnvrt, bastext or any other tokeniser / detokeniser / assembler. It’s all been written completely from scratch.

New features:

  • Debugger:
    • Keyboard shortcuts.
    • Instruction cycle counter.
    • Overlay files.
    • VICE Snapshot files (for C64 and VIC 20 only).
    • Better execution control, e.g. step over, into etc.
    • Change SP and SR registers.
    • Memory viewer.
    • Much better performance.
    • Updated tutorial.
  • Character editor:
    • Edited characters indicator.
    • Copy groups of characters.
    • Scroll the scratchpad.
  • BASIC:
    • Batch mode added.
    • Constants can be defined/redefined in code, and use hex values.
    • Auto line numbering inproved.

Bugs fixed:

  • ‘£’ was in invalid BASIC character.
  • $(nn),y was not being assembled properly, whereas ($nn),y was.
  • Casted offsets (offsets which are based on other offsets) were broken.
  • Problems renumbering BASIC programs with ON..GOTO/GOSUB with spaces in the line number list.
  • PC relative offsets (e.g. bvc *-2) fixed.
  • ‘Align’ directive not working.
  • Load/save in character editor.
  • Multicolour issues with the screen/character/sprite editors.
  • Including sprite files (IncBin) into assembly source only generated 63 bytes.

See the help for a complete list of new features and fixed bugs.

Download: CBM prg Studio v2.7.0 (940)

source: ajordison.co.uk

C64 Game: Trance Sector CE +10HFD / Glider Rider +4/D/P/TL …

July 12th, 2013 No comments

ITS Module: TAP player for the C64SD v2.0 (based on sd2iec)

July 11th, 2013 No comments
ITS TAP Module with C64SD v2.0

Autopsy:

I have to thank my friend Damiano for sending me the ITS Module with a low serial number, which like the previous one (C64SD v2.0) i really appreciate it.

The ITS module is a interface that enables SD2IEC to play .TAP files version 1 and version 2 to a commodore machine. The ITS module was designed to fit into the pass-through tape connector of C64SD Infinity and to be connected to the C64SD by a four wires cable that allows C64SD to manage it.

SD2IEC firmware has been modified in order to add the commands and the routines needed to control the external ITS module without removing any of the original SD2IEC functionalities

Features:

  • Play back any V1 or V2 standard .TAP files in order to load them into a commodore machine belonging to the “classic” or “264” series including: VIC-20, VC20, C64, C16, C116, C128 (all
  • versions) and Plus/4. Note: some models of C128D doesn’t have the tape edge-card connector, of  course ITS is not compatible with these machines.
  • Rebuild the original tape grabbed into all the .TAP version 1 and for most of the version 2
  • Work permanently connected between the tape port of the commodore computers and the corresponding datassette (either 1530 white model flat plug or 1531 black model mini-din plug) acting
  • As a pass-through transparent gateway or activated in order to play back .TAP files: no need to connect and disconnect the module to use your datassette.
  • Play back .TAP content with optimal accuracy and completely in digital format without the hassle of file conversions or level adjustment
  • Simulate tape motor activation logic fully so that the play back of the tape is managed as it would be in a real C2N tape. An override button has been provided able to stop the play back of the “virtual tape” at any time when necessary.
  • Work with either 1530 (White model, flat plug) datassette recorder as well as with 1531 (Black, mini-din plug) datassette
  • Load .TAP with multiple programs recorded one after the other (like the classic tape compilations sold in the 80′s)  

What Can’t You Do:

  • Create a .TAP file representing the content of a Tape (i.e. ITS is not a “tape content grabber”)
  • Fix the content of a TAP file in case it’s broken. Broken .TAP won’t load on your Commodore box. Since there are literally thousands of utilities to create and manipulate .TAP files there is the possibility to come across non-standard or incorrect .TAP files.
  • Play back the content of .TAP of version V0. Use an utility to convert V0 .TAP files to V1 such as TapClean then you will be able to use the converted .TAP file with ITS module.
  • Manage programs saved on tape that are based on the tape-counter management or on the time of wind-rewind of the tape.

The ITS Module can be purchased on the Manosoft site.

ITS Tape Loading video:

source: manosoft.it