MV-LED

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MV-LED board. Picture courtesy of [TheArcadeBoneyard].
MV-LED2 board, same components, different size. Picture courtesy of [MVS-Scans].

LED-based credits display board in original MVS cabs. Uses two 7-segment displays to show the player's remaining credits.

Uses CRE401 arrays for inputs.

Pinout, from left to right (pins 1 to 13):

  • 5V
  • 5V
  • Clock
  • Digit 1 ABCD
  • Digit 2 ABCD
  • GND
  • GND

Digits are BCD-coded and controlled by registers Reg.png REG_LEDLATCHES and Reg.png REG_LEDDATA.

74ls47 digits.png

See also MV-ELA for the marquee board details.

MV-LED2 board incomplete schematic.

Connection to the MVS board visible in [on page 5 of the schematics]

Repair

These boards can be tested in the system ROM's hardware test menu. The third screen shows "LED1" and "LED2" values which should change each second. The value shown should be the value displayed on the boards.