Reading the control register would automatically deassert .
The device is programmed with an address to write to (generally a control register in an interrupt controller), and a 16-bit data word to identify it.
Each buffer had a control register and status register to monitor its state and configure the raising of interrupts.
Doing so actuated a relay in the video hardware, and was accomplished by writing to a specific memory-mapped control register.
A control register is a processor register which changes or controls the general behavior of a CPU or other digital device.
The address lines A and A allow to successively access any one of the ports or the control register as listed below:
Allows omission of the expensive loading and re-loading of the control register in languages such as C where float-to-int conversion requires truncate behaviour by standard.
MIPS32 and MIPS64 define a control register set as well as the instruction set.
The Dazzler supported four graphics modes in total, selected by setting or clearing bits in the control register (0F) that controlled two orthogonal selections.
The control register controls the number of stop bits, the word length, receiver clock source and transmit/receive rate.