v0.2 · Author diagrams
Find a component and its ports
A compact reference for every circuit, logic, quantum, IC, and UML node.
01 / CircuitPassive components
The three passives — resistor, capacitor, and inductor — are fixed horizontal symbols. Whatever distinguishes one from the next (a value, a tolerance, a role) lives in the quoted label, not in the geometry.
| Kind | Left ports | Right ports | Options |
|---|---|---|---|
resistor |
in, left, l |
out, right, r |
None |
capacitor |
in, left, l |
out, right, r |
None |
inductor |
in, left, l |
out, right, r |
None |
port:IN "Input" at (55, 150) #blue
resistor:R1 "10 k\Omega" at (240, 150) #amber
inductor:L1 "22 \muH" at (450, 150) #purple
capacitor:C1 "100 nF" at (660, 150) #cyan
port:OUT "Output" at (845, 150) #emerald
IN.out -> R1.in #blue [line]
R1.out -> L1.in #amber [line]
L1.out -> C1.in #purple [line]
C1.out -> OUT.in #emerald [line marker-end=arrow]02 / CircuitDiodes and transistors
A diode keeps its anode on the left and cathode on the right; pick the flavor with type=standard|schottky|zener|led. A transistor takes type=npn|pnp|nmos|pmos, and — usefully — the BJT and FET names point at the same physical terminals, so you may wire it in whichever vocabulary you think in.
| Node | Ports |
|---|---|
diode |
anode/a, cathode/k/c |
transistor |
base/gate/b/g, collector/drain/c/d, emitter/source/e/s |
port:CTRL "Gate" at (70, 190) #blue
transistor:Q1 "2N7002" at (350, 190) #cyan [type=nmos]
diode:D1 "Clamp" at (590, 105) #purple [type=schottky]
port:OUT "Load" at (800, 105) #emerald
ground:GND "Ground" at (350, 325) #slate
CTRL.out -> Q1.gate #blue [line]
Q1.drain -> D1.anode #cyan [ortho]
D1.cathode -> OUT.in #emerald [line marker-end=arrow]
Q1.source -> GND.in #slate [ortho]03 / CircuitPorts and grounds
A port marks the edge of a system and exposes exactly in and out — nothing more, because an edge should not pretend to be a component. A ground carries a single in port above the symbol; choose style=signal, earth, or chassis, and signal is what you get when you say nothing.
port:VIN "Input" at (70, 100) #blue
resistor:R1 "1 M\Omega" at (320, 100) #amber
ground:GND "Reference" at (520, 240) #slate [style=earth]
VIN.out -> R1.in #blue [line]
R1.out -> GND.in #slate [ortho]04 / LogicClassical logic gates
The built-in gates are the six you would expect: and, nand, or, nor, xor, and not. Scale the fan-in and fan-out explicitly with inputs=1..32 and outputs=1..32, choose a standard=ieee|iec body, and remember that not always has exactly one input. Ports are in1..inN and out1..outN, with in and out aliasing the first pins for the common case.
port:A "A" at (60, 90) #blue
port:B "B" at (60, 250) #blue
xor:X1 "Parity" at (330, 170) #cyan [inputs=2 outputs=1]
not:N1 "Invert" at (590, 170) #amber [outputs=1 standard=iec]
port:Y "Y" at (800, 170) #emerald
A.out -> X1.in1 #blue [bezier]
B.out -> X1.in2 #blue [bezier]
X1.out -> N1.in #cyan [line]
N1.out -> Y.in #emerald [line marker-end=arrow]05 / QuantumQuantum gates
hadamard exposes in and out; cnot adds control and target; and qgate is the escape hatch — a custom operator block that accepts quoted parameter, matrix, and phase rows. As everywhere in schemd, every visible string supports micro-math, so an operator can wear its own definition.
port:QIN "|0〉" at (55, 200) #slate
hadamard:H1 "H" at (230, 200) #purple
qgate:RZ "R_z" at (440, 200) #cyan [parameter="\theta/2" phase="\pi/4"]
cnot:CX "CNOT" at (660, 200) #purple
port:QOUT "|1〉" at (880, 200) #emerald
port:CTRL "Control" at (660, 65) #blue
port:TARGET "Target" at (660, 335) #amber
QIN.out -> H1.in #slate [line]
H1.out -> RZ.in #purple [line]
RZ.out -> CX.in #cyan [line]
CX.out -> QOUT.in #emerald [line marker-end=arrow]
CTRL.out -> CX.control #blue [line]
CX.target -> TARGET.in #amber [line]06 / BlocksIntegrated circuits
ic takes quoted, comma-separated left, right, top, and bottom pin lists. Each name becomes a case-sensitive port, and the body grows to fit the longest side, so you never hand-size the box. Wire with the real pin name — U1.DATA — and let in/out fall back to the first suitable input and output sides when you genuinely do not care which.
port:INPUT "Sensor bus" at (60, 230) #blue
port:CLOCK "Clock" at (430, 60) #amber
ic:U1 "Flight computer" at (480, 240) #cyan [left="DATA,ENABLE,RESET" right="ACTUATOR,FAULT" top="CLK,VCC" bottom="GND,VSS"]
port:OUTPUT "Actuator" at (900, 220) #emerald
ground:GND "Reference" at (520, 410) #slate
INPUT.out -> U1.DATA #blue [ortho]
CLOCK.out -> U1.CLK #amber [ortho]
U1.ACTUATOR -> OUTPUT.in #emerald [ortho marker-end=arrow]
U1.GND -> GND.in #slate [ortho]07 / UMLClasses, packages, and notes
class accepts semicolon-separated attributes and operations, plus an optional stereotype and width. Its height grows with the rows and its width grows to fit the widest visible string — the compartment is always exactly as large as its contents demand, never a pixel of guesswork. package and note take width and height; they are ordinary nodes, not automatic layout containers, and that distinction is worth keeping straight. Every UML node exposes left, right, top, bottom, in, and out.
package:Domain "Domain" at (120, 70) #slate [width=160]
class:Order "Order" at (280, 215) #blue [attributes="- id: UUID; - total: Money" operations="+ submit(): void"]
class:LineItem "LineItem" at (720, 215) #emerald [attributes="- quantity: number"]
note:Rule "An order owns its items" at (480, 405) #amber [width=210]
Domain.bottom -> Order.top #slate [ortho dependency]
Order.right -> LineItem.left #emerald [ortho composition label="contains"]
Rule.top -> Order.bottom #amber [ortho dependency label="documents"]08 / UMLActors, use cases, states, and pseudostates
actor, initial, and final need no options at all. usecase accepts width and height; state accepts semicolon-separated details and an optional width. For the connectors, reach for association to show participation, include and extend between use cases, and transition for state flow — the same relationship grammar you met in the class diagram, doing behavioral work.
actor:Customer "Customer" at (80, 145) #blue
usecase:Checkout "Checkout" at (300, 145) #cyan
usecase:Auth "Authenticate" at (300, 310) #purple
state:Pending "Pending" at (590, 145) #amber [details="entry / reserve; exit / charge"]
initial:Start "Start" at (590, 330) #slate
final:Done "Done" at (820, 330) #emerald
Customer.right -> Checkout.left #blue [line association]
Checkout.bottom -> Auth.top #purple [ortho include]
Checkout.right -> Pending.left #amber [line transition label="submit"]
Start.right -> Done.left #emerald [line transition label="complete"]09 / UMLSequence lifelines and messages
lifeline accepts width and height, and — the detail that makes sequence diagrams actually work — alongside the usual side ports, leftNN and rightNN place a port exactly NN units below the top of the lifeline. Use message for an open arrow, add dashed for a reply, and label="..." for the message text itself.
lifeline:Client "Client" at (200, 220) #blue [width=140 height=320]
lifeline:API "Orders API" at (600, 220) #emerald [width=140 height=320]
Client.right80 -> API.left80 #blue [line message label="GET /orders"]
API.left160 -> Client.right160 #emerald [line message dashed label="200 OK"]