The PET 2001 and variants
PET 2001/CBM 2001: 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.
Designed on an appliance computer philosophy 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 had several limitations - not least the awful chiclet
keyboard that owed more to a calcular keypad than it did to a real
computer keyboard. As well, the original model had a non functional
IEEE 488 port - a shortcoming that was addresed in later models.
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.
Later upgraded models of the 2001 moved the Datasette outside the
case and this allowed for a "proper" full stroke keyboard on the main
unit. Internally a newer motherboard was used, along with an upgrade
from static memory to dynamic memory and 8, 16, or 32 KB, known as the
2001-N-8, 2001-N-16 or 2001-N-32, respectively.
This computer had different names depending on where in the world it was released. In the US market it was called a PET and in the European markets it was named the CBM3xxx series due to a competitor machine made by Philips already using the PET name. In Australia the original computers were distributed by Hanimex as Commodore did not havea local presence and the front badge did not have the Commodore logo, merely procaliming "CBM 2001". These original Australian machines had no Commodore naming anywhere on the external case but rather were branded (on the rear sticker) with the Hannimex name.
The PET name comes from the initials of "Personal Electronic
Transactor" and some sources claim that this was made up and that
Commodore was attempting to cash in on the Pet Rock fad that was
popular at the time. The "Transactor" name would live on in the form of
the popular magzine of the same name.
The heart of the PET was the MOS Technologies 6502 running at 1MHz
and designed by Chuck Peddle. Throughout this range of computers it
would remain as the CPU.
The display in all these models utilised a monochrome green screen
that although it had PETSCII graphics did not have sprites. All 2001
models had the same screen size.
Access to the computer internally was made exceedingly easy; the
whole monitor assembly lifted up on hinges to expose the roomy
motherboard and power supply.
The operating system for all machines was Commodore Basic, derived
from Microsoft Basic and sharing much in common with other personal
computers of the time. In a stroke of brialliance Jack Tramiel refused
to pay a per unit license fee and instead purchased the source
outright. Commodore from then on improved and re-wrote Basic
without being bound to Microsoft. Basic was included in ROM and was for
the most part rather slow.
The 2001's used three different versions of Basic; the origianl machine
had Version 1.0, next releases had Version 2.0 and the later 2001's
used Version 4.0
