M782 Interrupt Control
The M782 Interrupt Control (later versions M7820 and M7821) is a DEC FLIP CHIP which implements the 'interrupt control' function for the UNIBUS.
It was used, along with an M105 Address Selector, in early PDP-11 device controllers which plugged into an SPC slot. It was also used in a number of early devices which were built out of a custom backplane and a large number of FLIP CHIPs, such as the RK11-C. Some later devices which no longer used a large number of small Flip Chips (such as the TMB11) also used it.
The board contained a number of jumpers which could be use to set the interrupt vector. The M7820 can set vector address bits 2-8 (i.e. vectors of the form 0xx0 and 0xx4); bit 2 (04) can be controller be either the device's electronics, or the jumper.
