KWV11-C programmable real-time clock
From Computer History Wiki
The KWV11-C programmable real-time clock is a QBUS clock module, very similar in functionality to the KW11-P Programmable Real-Time Clock. It can either provide interval counting, or produce either single or repeated interrupts at a programmed rate (at a multiple of the base rate). Several different clock rates, five of them internal, are available:
- 1 MHz
- 100 KHz
- 10 KHz
- 1 KHz
- 100 Hz
- line rate from the AC power provided to the power supply
- external
The programming interface is fairly simple; there are two registers:
- control/status
- buffer/preset
The counter register can be set to count up, governed by the selected rate; an interrupt can be triggered when it reaches 0 on overflow. It can then optionally be automatically reloaded from the preset register.
Physically, the KW11-P is an dual-height board (M4002).
External links
- LSI-11 Analog System User's Guide (EK-AXV11-UG-002) - the KWV11-C is covered in Chapter 5
- Microsystems Options (EK-192AA-MG-001) - configuration of the KWV11-C is covered on pp. 144-149 of the PDF
