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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.
* Please note the board Errata sheet * (Kicad 4 does not connect signals exiting a global bus to traces of the same name on the same sheet.)
|ProtoBoard III schematic||219Kb||21-Oct-2017|
|ProtoBoard III parts list||18Kb||12-Mar-2017|
|Jameco Part numbers||1kb||18-Feb-2017|
|Photos from Kicad||5.4Mb||02-Feb-2017|
|Kicad 4.4.0 project files||625Kb||02-Feb-2017|
|ProtoBoard III errata - mandatory||24Kb||04-Oct-2017|
This board is licensed for hobbyist use only.