2-Phase-4-Phase Converter

Specifications

Informal

A 2-Phase-4-Phase Converter has two input terminals (a and d) and two output terminals (b and c). Input a and output b alternate (together forming a passive handshake channel), as do output c and input d (together forming an active handshake channel). Every 2 phases ab enclose 4 phases cdcd.

XDI

Schematic diagram for a 2-Phase-4-Phase Converter:

[Zoom|FIG]

XDI state graph for a 2-Phase-4-Phase Converter:

[Zoom|FIG]

Specification in XDI model.

Verdect

Specification in Verdect:


define PC24( a?, b!, c!, d? ) =
       pref *[ a? ; c! ; d? ; c! ; d? ; b! ]
end

Also available through this link

DI Algebra

Specification in DI Algebra:


NAME = "2-Phase-4-Phase-Converter"
I = { a?, d? }
O = { b!, c! }

Q = [a? -> c!; R
    ,d? -> CHAOS
    ]
R = [d? -> c!; S
    ,a? -> CHAOS
    ]
S = [d? -> b!; Q
    ,a? -> CHAOS
    ]

Also available through this link

Properties

XDI Report.

Implementations

DI Decompositions

A 2-Phase-4-Phase Converter QR24(a,b,c,d) can be implemented using a Merge(a,x,c) and a Toggle(d,x,b) (not equ):

[Zoom|FIG]
The following implementation closely resembles that of the 4-Phase-2-Phase Converter, uses a Fork(a,f0,f1), a Merge(f0,t0,c), a Join(f1,t1,b) and a Toggle(d,t0,t1) (not equ) and is hence unnecessarily expensive:

[Zoom|FIG]