The PDP-7, introduced in 1965, was DEC's third 18-bit computer system. Both faster and less expensive than the PDP-1, the PDP-7 maintained upward compatibility from the PDP-4 but introduced many new options, including extended memory, extended arithmetic capability, and a crude form of memory protection. The PDP-7 featured the 18b product line's first mass storage operating system (DECsys, based on DECtapes). It was also the development system for the first versions of UNIX.
Photographs (courtesy of Digital Equipment Corporation):
| Option | Description | Capacity |
| CPU and memory | PDP-7 | 4KW - 32KW |
| CPU options | Type 177 EAE, extended arithmetic element | |
| Type 148 memory extension control | ||
| Console | Type 649 KSR-33 Teletype | |
| Paper tape | Type 444 paper tape reader | |
| Type 75 paper tape punch | ||
| Real-time clock | integral | |
| Line printer | Type 647B line printer (sixbit ASCII) | |
| DECtape | Type 550/555 DECtape | 148KW |
| Drum | Type 24 serial drum | 131KW |
| Disk | RB09 fixed-head disk | 1024KW |
Updated 08-Aug-2020 by Bob Supnik (simh AT groups DOT io - anti-spam encoded)
