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ProtoBoard III – ECB bus prototyping card


This board fixes the I/O select problem on former boards, which did not qualify /IORQ with /M1 high. This extra qualification prevents the board from selecting on an INTA (Interrupt Acknowledge) cycle.

The board may be constructed with either the 74LS682 (preferred), 74LS684, or 74LS688 chip. The last two require a strip of 22K bussed resistors; the first does not.


The current version is 17-10-05

Gerbers are here :

Please note errata for previous version here.


Board Description 770Kb12-Mar-2017
ProtoBoard III schematic 219Kb21-Oct-2017
ProtoBoard III parts list 18Kb12-Mar-2017
Jameco Part numbers 1kb18-Feb-2017
Photos from Kicad 5.4Mb02-Feb-2017
Kicad 4.4.0 project files 625Kb02-Feb-2017
ProtoBoard III errata - mandatory 24Kb04-Oct-2017

This board is licensed for hobbyist use only.

boards/ecb/protoboard_iii/protoboard_iii.1616211593.txt.gz · Last modified: 2021/03/19 23:39 by b1ackmai1er
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