GLOSSARY

program memory

A partition of memory where instructions can be

 

 

stored for fetching and execution.

protected instruction

An instruction that prevents an interrupt from being

 

 

acknowledged until after the next instruction

 

 

executes. The protected instructions are DI, EI, DPTS,

 

 

EPTS, POPA, POPF, PUSHA, and PUSHF.

PSW

Processor status word. The high byte of the PSW is

 

 

the status byte, which contains one bit that globally

 

 

enables or disables servicing of all maskable

 

 

interrupts, one bit that enables or disables the PTS,

 

 

and six Boolean flags that reflect the state of the

 

 

current program. The low byte of the PSW is the

 

 

INT_MASK register. A push or pop instruction saves

 

 

or restores both bytes (PSW + INT_MASK).

PTS

Peripheral transaction server. The microcoded

 

 

hardware interrupt processor.

PTSCB

See PTS control block.

PTS control block

A block of data required for each PTS interrupt. The

 

 

microcode executes the proper PTS routine based on

 

 

the contents of the PTS control block.

PTS cycle

The microcoded response to a single PTS interrupt

 

 

request.

PTS interrupt

Any maskable interrupt that is assigned to the PTS for

 

 

interrupt processing.

PTS mode

A microcoded response that enables the PTS to

 

 

complete a specific task quickly. These tasks include

 

 

transferring a single byte or word, transferring a block

 

 

of bytes or words, managing multiple A/D conver-

 

 

sions, and generating PWM outputs.

PTS routine

The entire microcoded response to multiple PTS

 

 

interrupt requests. The PTS routine is controlled by

 

 

the contents of the PTS control block.

PTS transfer

The movement of a single byte or word from the

 

 

source memory location to the destination memory

 

 

location.

PTS vector

A location in special-purpose memory that holds the

 

 

starting address of a PTS control block.

 

 

Glossary-7

 

 

 

 

 

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Intel 8XC196MD, 8XC196MH, 8XC196MC manual Pts