The first Pascal compiler was developed during the years 1969-1971 for Control Data 6000 series hardware at the Institut für Informatik, Eidgenössische Technische Hochschule Zürich. As result of experience with the system and a new implementation begun in July, 1972, resulting in a family of two compilers, Pascal_P and Pascal-6000, having a single overall design.
Pascal-P is a portable compiler that produces code for a hypothetical stack computer, the system is implemented by writing an interpreter for this machine.
Pascal-6000 produces relocatable code for Contrl Data 600 series computers.
Descendants of these two compilers comprised the bulk of the Pascal implementations in existence after 1980.
CDC 6000 Pascal compilers