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Synchronous Address Multiplexer

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Synchronous Address Multiplexer

Supports the MC6809/HD6309 MPU interleaving memory access with the MC6847/MC6847T1 VDG and the dynamic RAM refresh cycles.

Variants

  • SN74LS783 / MC6883 - used in CoCo 1/2
  • SN74LS785 - used in CoCo 2B
  • SAM Accelerator - an accelerated SAM allowing RAM refresh during full double-speed clock mode on CoCo 1/2 (may require upgraded PIAs too)
  • SAMX4 - CPLD-based SAM replacement with additional 256K banking
  • TCC1014 1986 - the 1986 version of the ACVC / GIME replaces and includes much of the SAM functionality for CoCo 1/2 backwards compatibility support
  • TCC1014 1987 - the 1987 version of the ACVC / GIME also replaces and includes much of the SAM functionality for CoCO 1/2 backwards compatibility support