ChipsI/O & supportTimers, interrupts & DMA › Motorola 6840 PTM

Motorola 6840 PTM

1979

Motorola's Programmable Timer Module, providing three 16-bit counter/timers for 6800-family systems.

Reference & documentation

External technical references for programming Motorola 6840 PTM and for writing emulators.

ResourceTypeNotes
MC6840 Programmable Timer Module - Motorola Manual (bitsavers) ↗DatasheetCanonical Motorola PTM manual: full electricals and timing
MC6840 Programmable Timer Module datasheet (Color Computer Archive) ↗DatasheetClean scanned PTM datasheet mirror
MC6840 datasheet (AllDatasheet, 14-page PDF) ↗DatasheetBrowsable HTML plus PDF of PTM datasheet
MC6840 Manual - Status Register and Interrupts ↗Interrupt listStatus register flags and composite IRQ generation
MAME ptm6840_device header (6840ptm.h) ↗Memory mapEight register offsets, callbacks and device interface
MC6840 Manual - Pinout and Bus Interface ↗Pinout28-pin DIP signals, chip-select and register-select lines
MC6840 Manual - Control/Timer Register Programming ↗ProgrammingControl register bits, timer modes, gate/clock behaviour
MC6840 PTM datasheet (l'impulsion mirror) ↗ReferenceAlternate PTM datasheet mirror for cross-checking specs
MAME ptm6840_device implementation (6840ptm.cpp) ↗SourceReference C++ emulation of all three timer modes