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Archive for the ‘Commodore CBM/PET family’ Category

Commodore CBM (PET) 3032 – Repair and Restoration

September 5th, 2012 No comments

This is the story of a Commodore CBM (PET) 3032 recovered in a pitiful state.

The motherboard was covered of rust and many IC are in short circuit. I had to replace some IC (broken or full of rust), rebuild some paths of the pcb and clean very well.

I have also restored the inside of the case, using an anti-rust gel painting.

Photos and Description of the work made:

Read more…

Commodore CBM (PET) 3032

September 5th, 2012 No comments
Commodore CBM (PET) 3032

Autopsy:

The Commodore CBM (PET) 3032 is a successor to the Commodore PET 2001, it has a bigger keyboard and 32KB dynamic RAM memory. The larger keyboard means that the first cassette drive now has to be an external unit.

from Wikipedia:

The Commodore PET (Personal Electronic Transactor) was a home/personal computer produced from 1977 by Commodore International. A top-seller in the Canadian and United States educational markets, it was Commodore’s first full-featured computer, and formed the basis for their entire 8-bit product line.

The PET 2001 was announced at the Winter CES in January 1977 and the first 100 units were shipped later that year in October. However, the PET was back-ordered for months and to ease deliveries, early in 1978 Commodore decided to cancel the 4 kB version (also because the user would be left with barely 3 kB of RAM).

Although the machine was fairly successful, there were frequent complaints about the tiny calculator-like keyboard, often referred to as a “chiclet keyboard” because the keys resembled the gum candy. The key tops also tended to rub off easily. Reliability was fairly poor, although that was not atypical of many early microcomputers. Because of the poor keyboard on the PET, external replacement ones quickly appeared.

In 1979, Commodore replaced the original PET 2001 with an improved model known as the 2001-N (the N was short for “New”). The new machine used a standard green-phosphor monitor in place of the light blue in the original 2001. It now had a conventional, full-sized keyboard and no longer sported the built-in cassette recorder. The kernel ROM was upgraded to add support for Commodore’s newly-introduced disk drive line. It was offered in 8kB, 16kB, or 32kB models as the 2001-N8, 2001-N16, and 2001-N32 (the 8kB models were dropped soon after introduction). Finally, Commodore added a machine-language monitor to the kernel ROM that could be accessed by jumping to any memory location with a BRK instruction. It did not include a built-in assembler and required the user to enter hexadecimal numbers for coding.

Sales of the newer machines were strong, and Commodore then introduced the models to Europe. The result was the CBM 3000 series (‘CBM’ standing for Commodore Business Machines), which included the 3008, 3016 and 3032 models. Like the 2001-N-8, the 3008 was quickly dropped. The change to CBM occurred because of a trademark dispute with Philips over the PET name.

source: wikipedia

Commodore PET 8296-D

December 4th, 2011 9 comments
Commodore PET 8296-D

Autopsy:

from Wikipedia:

The Commodore PET (Personal Electronic Transactor) was a home/personal computer produced from 1977 by Commodore International. A top-seller in the Canadian and United States educational markets, it was Commodore’s first full-featured computer, and formed the basis for their entire 8-bit product line.

The PET 2001 was announced at the Winter CES in January 1977 and the first 100 units were shipped later that year in October. However, the PET was back-ordered for months and to ease deliveries, early in 1978 Commodore decided to cancel the 4 kB version.

Although the machine was fairly successful, there were frequent complaints about the tiny calculator-like keyboard, often referred to as a “chiclet keyboard” because the keys resembled the gum candy. This was addressed in upgraded “dash N” and “dash B” versions of the 2001, which put the cassette tape recorder outside the case, and included a much larger keyboard with a full stroke motion. Internally a newer motherboard was used, along with an upgrade from static RAM to dynamic RAM and 8, 16, or 32 KB, known as the 2001-N-8, 2001-N-16 or 2001-N-32, respectively.

Sales of the newer machines were strong, and Commodore then introduced the models to Europe. The result was the CBM 3000 series (‘CBM’ standing for Commodore Business Machines), which included the 3008, 3016 and 3032 models. Like the 2001-N-8, the 3008 was quickly dropped.

The final version of what could be thought of as the “classic” PET was the PET 4000 series. This was essentially the later model 2000 series, but with a larger black-and-green monitor and a newer version of Commodore’s BASIC programming language.

Commodore tried to update the PET line with a new redesign called the CBM-II series (also known as the B series). These were not as successful and were ultimately abandoned. However, due to demand, the original PET machines were revived and the CBM-II case style was retained. These were known as the SK’s (due to the separated keyboard). They also had a swivel monitor. Originally, standard 8032 boards were retrofitted into these cases. Later the SK models got a new mainboard that already included the 64 kB extension directly on the board and were sold as 8296 or, with a built-in 8250 dual disk drive, as 8296-D.

source: wikipedia

Commodore PET 4032 (Fat 40)

November 30th, 2011 No comments
Commodore PET 4032 (Fat 40)

Autopsy:

from Wikipedia:

The Commodore PET (Personal Electronic Transactor) was a home/personal computer produced from 1977 by Commodore International. A top-seller in the Canadian and United States educational markets, it was Commodore’s first full-featured computer, and formed the basis for their entire 8-bit product line.

The PET 2001 was announced at the Winter CES in January 1977 and the first 100 units were shipped later that year in October. However, the PET was back-ordered for months and to ease deliveries, early in 1978 Commodore decided to cancel the 4 kB version.

Although the machine was fairly successful, there were frequent complaints about the tiny calculator-like keyboard, often referred to as a “chiclet keyboard” because the keys resembled the gum candy. This was addressed in upgraded “dash N” and “dash B” versions of the 2001, which put the cassette tape recorder outside the case, and included a much larger keyboard with a full stroke motion. Internally a newer motherboard was used, along with an upgrade from static RAM to dynamic RAM and 8, 16, or 32 KB, known as the 2001-N-8, 2001-N-16 or 2001-N-32, respectively.

Sales of the newer machines were strong, and Commodore then introduced the models to Europe. The result was the CBM 3000 series (‘CBM’ standing for Commodore Business Machines), which included the 3008, 3016 and 3032 models. Like the 2001-N-8, the 3008 was quickly dropped.

The final version of what could be thought of as the “classic” PET was the PET 4000 series. This was essentially the later model 2000 series, but with a larger black-and-green monitor and a newer version of Commodore’s BASIC programming language.

source: wikipedia

My homebrew C2N232 Interface

March 20th, 2010 No comments
Marko Mäkelä's C2N232 interface

Autopsy:

This is my homebrew C2N232 Interface.

from Marko Mäkelä’s homepage:

The C2N232 is a small RS-232 interface that can be plugged to the cassette port of an 8-bit Commodore computer:

  • PET series: 2001, 3000 series, 4000 series, 8000 series, 200 series
  • PET-II series: CBM 500, 600 or 700 series (P500 or the B series)
  • Commodore VC-20, VIC-20 or VIC-1001
  • Commodore 64, 4064, 64c or 64G
  • Commodore 128, 128D or 128DCR
  • Commodore 264 series: 16, 116, plus/4 or 232

source: Marko Mäkelä’s Homepage

Commodore CBM 8250 Dual Drive Floppy Disk

March 17th, 2010 No comments
Floppy Disk Drive CBM 8250

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

Commodore PET CBM 8096-SK (Low serial number: WG #01234)

March 15th, 2010 5 comments
Commodore PET CBM 8096-SK

Autopsy:

from Wikipedia:

The Commodore PET (Personal Electronic Transactor) was a home/personal computer produced by Commodore starting in 1977.  It was a top seller in the Canadian, United States, and United Kingdom educational markets, and was Commodore’s first full-featured computer and would form the basis for their entire 8-bit  platform. n the 1970s, Texas Instruments was the main supplier of CPUs for use in calculators. Many companies sold calculator designs based on their chip sets, including Commodore.

However, in 1975 TI increased the price to the point where the chip set alone cost more than what TI sold their entire calculators for, and the industry they had built up was frozen out of the market. Commodore responded by looking for a chip set of their own they could purchase outright, and quickly found MOS Technology, Inc. who were bringing their 6502 microprocessor design to market.

Along with the company came Chuck Peddle’s KIM-1 design, a small computer kit based on the 6502. At Commodore, Peddle convinced Jack Tramiel that calculators were a dead-end. Instead they should focus on making a “real” machine out of the KIM-1, and selling that for much higher profits. Tramiel demanded that Peddle, and Tramiel’s son, Leonard, create a computer in time for the June 1977 Consumer Electronics Show, and gave them six months to do it. The result was the first all-in-one home computer, the PET. The first model was the PET 2001, including either 4 KB (the 2001-4) or 8 KB (2001-8) of 8-bit RAM. It was essentially a single-board computer with discrete logic driving a small built-in monochrome monitor with 40×25 character graphics.

The machine also included a built-in Datassette for data storage located on the front of the case, which left little room for the keyboard. The data transfer rate to cassette was 1500 baud, duplicated for safety, giving an effective rate of 750 baud. The 2001 was announced at the ’77 Winter CES in January 1977 and the first 100 units were shipped in mid October 1977. However they remained back-ordered for months, and to ease deliveries they eventually cancelled the 4 kB version early the next year. Two more machines were released in the PET series.

The CBM 8000  included a new display chip which drove an 80×25 character screen, but this resulted in a number of software incompatibilities with programs designed for the 40 column screen, and it appears to have been unpopular as a result. The machine shipped with 32 kB standard as the 8032, but allowed another 64 kB to be added externally. Later the upgrade was installed from the factory, creating the 8096.

source: wikipedia petlibrary.tripod.com

Commodore Modem 8010 Powersupply pinouts

August 31st, 2009 1 comment

din5m

  • PIN 1 = Common (GND)
  • PIN 4 = Free
  • PIN 2 = 14.6v (AC)
  • PIN 5 = Free
  • PIN 3 = 14.6v (AC)

Click here for my Commodore Modem 8010.

Commodore Modem Model 8010

May 12th, 2009 9 comments
Commodore Modem Model 8010

autopsy:

This is my first Modem, this is a Acoustic coupler modem for Commodore PET but i could use it with a IEEE488 Interface for the Commodore 64.

The Commodore’s 8010 Modem is an IEEE-488 (1978 standard) device which communicates via any standard telephone.

The 8010 Modem meets Bell 103 standards for communication at a fixed rate of  00 BAUD. The telephone interface is acoustic so the modem is portable. This means Commodore computers can communicate with, large computer systems like The Source and MICRONET, and other small computers.

Initially Commodore supplied software will support the following applications, with many more to come.

1) Terminal emulation.
2) Disk file send and receive.
3) Wordpro 3 sequential file send.
4) Hardcopy using Commodore printers.
5) Disk spooling.

A switchable four-section bandpass filter provides out-of-band rejection assuring accurate processing of the input from received carrier, even at signal levels of less than -47 dBm.

Jitter-free data is guaranteed by a soft limiter and phase lock loop discriminator. The carrier detect circuitry prevents the CBM Modem from operating when excessive noise would produce errors or cause marginal operation. This feature also assures accurate teleprocessing connections and inhibits chatter when the received signal fades.

Commodore C2N – Original PET Style

April 22nd, 2009 1 comment

Autopsy:

Description:

  • Country: USA
  • Most Common: Usa/Europe
  • Rarity: Rare
  • Year: 1977

from Wikipedia:

The Commodore 1530 (C2N) Datasette, was Commodore’s dedicated computer tape recorder.

It provided access to an inexpensive storage medium for Commodore’s 8-bit home/personal computers, notably the PET, VIC-20, and C64. A physically similar model Commodore 1531 was made for the Commodore 16 and Plus/4 series computers.

The Datasette contained built-in analog to digital converters and audio filters to convert the computer’s digital information into analog sound and vice versa (much like a modem does over a telephone line). Connection to the computer was done via a proprietary edge connector (Commodore 1530) or mini-DIN connector (Commodore 1531). The absence of recordable audio signals on this interface made the Datasette and its few clones the only cassette recorders usable with CBM’s machines, until aftermarket converters made the use of ordinary recorders possible.

source: wikipedia