Control Unit Wiring Guide

Power (+5V / +3V3) — red kit wire Ground — blue kit wire I²C bus (SCL / SDA / IRQ) — yellow kit wire Signal (per-pin GPIO) — white / orange / green kit wire

Using the jumper wire kit

You're wiring this with a pre-formed solid-core jumper kit (the boxed assortment of red/yellow/white/orange/green/blue wires, fixed pre-cut lengths, ends bent square) — the standard kit sold for solderless breadboards. That matters for a few reasons specific to this board:

These wires are made for solderless boards — this perfboard isn't one. The bent tip is shaped to grip a breadboard's spring clip, not to make a reliable joint on its own. It will friction-fit into a perfboard hole and feel "connected," but it isn't electrically sound until soldered. Treat every insertion as a dry-fit, not a finished connection:

Push the wire's tip through the two holes the guide calls out (component-side/top of the board), and check the fit against the grid ref before committing.
Flip the board to the copper/solder side and solder both tips to their pads. A perfboard pad is just a ring of copper around the hole — feed a little solder onto the joint so it wets the ring, not just the wire.
Clip the excess tip flush once the joint has cooled.

The kit's lengths are fixed — the "rail" runs below are not. A shared bus row (GND/+3V3/+5V/SCL/SDA, see Shared bus rails below) usually spans more holes than any single wire in the kit. Two options, both fine:

Pick the longest wire that reaches and let it bow slightly between holes — solid core holds its shape, it won't spring back.
Daisy-chain shorter wires hole-to-hole along the row: at every intermediate hole, both the incoming and outgoing wire tips land in the same hole and both get soldered there together with the pad. Don't skip soldering an intermediate joint just because the wire "looks continuous" — each hole is a separate solder joint, there's no copper trace linking adjacent holes on bare perfboard.

The solder checklist already lists each rail hop separately, with its length in millimetres, so you can match a hop to a wire in the box before cutting anything.

Colour convention (matches the legend above, the kit's actual colours, and the 3D-modelled wires on the board): red for every +5V/+3V3 connection, blue for every GND connection (the kit has no black — blue is the closest "stay off the power colours" choice and reads unambiguously once you commit to it), yellow for the SCL/SDA/IRQ bus, and white/orange/green for the remaining signal wires. Each signal net gets one fixed colour, so the same wire is the same colour everywhere it appears — on this page, on the diagram, and in the 3D render. The checklist's colour column is the authority.

Test before you solder the far end. The small compartment of premade spade/hook-tipped leads in the kit box is handy for exactly this: clip one onto a wire you've already soldered at one end and touch the other lead to the destination pad with a multimeter in continuity mode, confirming against the grid ref, before soldering the second end permanently.

Back-side wiring diagram

The board seen from the solder side (mirrored), with every jumper drawn where it actually runs on the finished board. Wires that cross are drawn in physical over/under order.

power (+5V / +3V3) ground I²C bus (SCL / SDA / IRQ) signal — white signal — orange signal — green

The Teensy header sockets aren't outlined (48 near-parallel verticals would crowd the top of the diagram) — every net still ends at its correct header column. Signal colours are per net, not per connector group, so two adjacent wires can share a colour; cross-check the net name in the tables below.

Teensy header pinout

The two 24-pin sockets the Teensy drops into, drawn left to right as they sit on the board. Each cell shows the socket pin number, the perfboard hole under it, the Teensy net, and what this build wires to it. Greyed cells are unused — free for later expansion.

Header A — board row 23 (upper socket)

pin 1 at the left edge — the Teensy's USB end

1B23GNDrail

2A23D0B1.2

3Z23D1B2.2

4Y23D2S1.6

5X23D3S2.6

6W23D4B3.2

7V23D5R1.2

8U23D6CB2.1

9T23D7S3.6

10S23D8B4.2

11R23D9B8.2

12Q23D10NP1.4

13P23D11NP1.8

14O23D12S4.6

15N23+3V3rail

16M23D24NP1.7

17L23D25NP1.6

18K23D26B7.2

19J23D27S5.6

20I23D28NP1.5

21H23D29R5.2

22G23D30B6.2

23F23D31S6.6

24E23D32B5.2

Header B — board row 29 (lower socket)

pin 1 at the left edge — the Teensy's USB end

1B29+5Vrail

2A29GNDrail

3Z29+3V3rail

4Y29D23CB1.1

5X29D22J1.1

6W29D21J1.2

7V29D20J1.3

8U29D19—

9T29D18—

10S29D17R2.2

11R29D16J1.4

12Q29D15R3.2

13P29D14CB3.1

14O29D13R4.2

15N29GNDrail

16M29D41J2.4

17L29D40J2.3

18K29D39J2.2

19J29D38CB4.1

20I29D37J2.1

21H29D36NP1.3

22G29D35NP1.2

23F29D34CB5.1

24E29D33NP1.1

Shared bus rails

Five nets touch many holes each. Run each as one continuous chain past every hole listed, in the order listed (that's board order, top to bottom), rather than home-running each connector back to the header separately.

GND · 30 taps · blue wire

D11 Y11 T11 O11 J11 E11 A11 D16 Z16 V16 R16 O16 K16 G16 C16 B23 A29 N29 X35 I35 Z44 U44 P44 K44 F44 Z46 U46 P46 K46 F46

+3V3 · 11 taps · red wire

A10 D10 Y10 T10 O10 J10 E10 M13 H13 N23 Z29

+5V · 8 taps · red wire

A09 D09 Y09 T09 O09 J09 E09 B29

SDA · 9 taps · yellow wire

A08 D08 Y08 T08 O08 J08 E08 Q13 T29

SCL · 9 taps · yellow wire

A07 D07 Y07 T07 O07 J07 E07 L13 U29

Test points

Five male 2.54mm header pins in the last column past S6 (column A — the letter sequence wraps back to A at the board's right edge), tapping the same rails S1–S6 share. Clip a jumper or scope hook straight onto a pin instead of back-probing a live JST connector.

TP2 · SCL

A07

TP1 · SDA

A08

TP5 · +5V

A09

TP4 · +3V3

A10

TP3 · GND

A11

Connectors

S1–S6 — haptic drivers (I²C)

Rotated vertical, one per column, centred on the board. GND/+3V3/+5V/SDA/SCL all fall on the same row across all six — a horizontal bus wire along that row reaches every connector. Only pin 6 (IRQ) is unique per connector.

S1JST-XH-6 · col D

1	D11	GND	GND rail
2	D10	+3V3	+3V3 rail
3	D09	+5V	+5V rail
4	D08	SDA	SDA rail
5	D07	SCL	SCL rail
6	D06	IRQ1	D2 → Y23

S2JST-XH-6 · col Y

1	Y11	GND	GND rail
2	Y10	+3V3	+3V3 rail
3	Y09	+5V	+5V rail
4	Y08	SDA	SDA rail
5	Y07	SCL	SCL rail
6	Y06	IRQ2	D3 → X23

S3JST-XH-6 · col T

1	T11	GND	GND rail
2	T10	+3V3	+3V3 rail
3	T09	+5V	+5V rail
4	T08	SDA	SDA rail
5	T07	SCL	SCL rail
6	T06	IRQ3	D7 → T23

S4JST-XH-6 · col O

1	O11	GND	GND rail
2	O10	+3V3	+3V3 rail
3	O09	+5V	+5V rail
4	O08	SDA	SDA rail
5	O07	SCL	SCL rail
6	O06	IRQ4	D12 → O23

S5JST-XH-6 · col J

1	J11	GND	GND rail
2	J10	+3V3	+3V3 rail
3	J09	+5V	+5V rail
4	J08	SDA	SDA rail
5	J07	SCL	SCL rail
6	J06	IRQ5	D27 → J23

S6JST-XH-6 · col E

1	E11	GND	GND rail
2	E10	+3V3	+3V3 rail
3	E09	+5V	+5V rail
4	E08	SDA	SDA rail
5	E07	SCL	SCL rail
6	E06	IRQ6	D31 → F23

R12 / R13 — I²C pull-ups

Sit just below the S-zone, tapping the SDA/SCL/+3V3 rails directly. 4.7 kΩ each.

R124.7 kΩ · row 13

1	Q13	SDA	SDA rail
2	M13	+3V3	+3V3 rail

R134.7 kΩ · row 13

1	L13	SCL	SCL rail
2	H13	+3V3	+3V3 rail

B1–B8 — diamond buttons (mirrored)

B1–B4 (left cluster) mirror B5–B8 (right cluster) on the same row band, so left to right the refs read B1 B2 B3 B4 B8 B7 B6 B5 — the cards below are in that physical order, not numeric order. All eight pin-1 (GND) holes share one row: a single wire down that row grounds all eight.

B1JST-XH-2 · col D

1	D16	GND	GND rail
2	D15	B1	D0 → A23

B2JST-XH-2 · col Z

1	Z16	GND	GND rail
2	Z15	B2	D1 → Z23

B3JST-XH-2 · col V

1	V16	GND	GND rail
2	V15	B3	D4 → W23

B4JST-XH-2 · col R

1	R16	GND	GND rail
2	R15	B4	D8 → S23

B8JST-XH-2 · col O

1	O16	GND	GND rail
2	O15	B8	D9 → R23

B7JST-XH-2 · col K

1	K16	GND	GND rail
2	K15	B7	D26 → K23

B6JST-XH-2 · col G

1	G16	GND	GND rail
2	G15	B6	D30 → G23

B5JST-XH-2 · col C

1	C16	GND	GND rail
2	C15	B5	D32 → E23

J1 / J2 — joysticks (mirrored)

J1 (left stick) mirrors J2 (right stick); pin 5 (GND) on both lands on the same row.

J1JST-XH-5 · col X

1	X39	J1.1	D22 → X29
2	X38	J1.2	D21 → W29
3	X37	J1.3	D20 → V29
4	X36	J1.4	D16 → R29
5	X35	GND	GND rail

J2JST-XH-5 · col I

1	I39	J2.1	D37 → I29
2	I38	J2.2	D39 → K29
3	I37	J2.3	D40 → L29
4	I36	J2.4	D41 → M29
5	I35	GND	GND rail

CB1–CB5 — LED buttons (near-symmetric)

CB3 sits on the centre column; CB2/CB4 and CB1/CB5 mirror around it. Pin 3 is the LED anode and does not go to the Teensy — it goes to that connector's series resistor in the next column across, and the resistor's far end carries the GPIO. Both GND pins (2 and 4) sit on their own rows across all five. CB4's lamp is on D13, the Teensy's onboard-LED pin — safe only because a lamp is a driven output; never move a switch (pulled-up input) onto that pin.

CB1JST-XH-4 · col Z

1	Z47	CB1	D23 → Y29
2	Z46	GND	GND rail
3	Z45	LED_ARM	→ R1.1 A45
4	Z44	GND	GND rail

CB2JST-XH-4 · col U

1	U47	CB2	D6 → U23
2	U46	GND	GND rail
3	U45	LED_EN	→ R2.1 T45
4	U44	GND	GND rail

CB3JST-XH-4 · col P

1	P47	CB3	D14 → P29
2	P46	GND	GND rail
3	P45	LED_SFT	→ R3.1 Q45
4	P44	GND	GND rail

CB4JST-XH-4 · col K

1	K47	CB4	D38 → J29
2	K46	GND	GND rail
3	K45	LED_CONF	→ R4.1 L45
4	K44	GND	GND rail

CB5JST-XH-4 · col F

1	F47	CB5	D34 → F29
2	F46	GND	GND rail
3	F45	LED_ALT	→ R5.1 E45
4	F44	GND	GND rail

R1–R5 — LED series resistors

Standing upright in the column beside their own connector, pin 1 on row 45 — the same row as that connector's pin 3 — and pin 2 four holes up on row 41, pointing at the Teensy header. R2 and R5 sit one column to the right of their CB; R1, R3 and R4 one column to the left. That puts every LED-cathode jumper at a single 2.6 mm hole-to-hole hop (CB1.3 Z45 → R1.1 A45 and so on) instead of the 25–50 mm runs the old row-48 placement needed.

R1220 Ω · col A

1	A45	LED_ARM	← CB1.3 Z45
2	A41	LED1	D5 → V23

R2220 Ω · col T

1	T45	LED_EN	← CB2.3 U45
2	T41	LED2	D17 → S29

R3220 Ω · col Q

1	Q45	LED_SFT	← CB3.3 P45
2	Q41	LED3	D15 → Q29

R4220 Ω · col L

1	L45	LED_CONF	← CB4.3 K45
2	L41	LED4	D13 → O29

R5220 Ω · col E

1	E45	LED_ALT	← CB5.3 F45
2	E41	LED5	D29 → H23

NP1 — numpad

Pushed to the board's right edge to clear the Teensy header rows it shares rows with. Watch the labels here: the board's 32-column letter sequence reuses each letter at both ends, so NP1's holes can compute to the same letter+row as a header hole at the opposite edge. Use the left/right position, not the label alone. No numpad conductor is on D13 any more — that pin drives CB4's lamp. It stays reserved for driven outputs either way: the Teensy's onboard LED hangs off D13 and would fight a pull-up, so a column line must never be moved onto it.

NP1JST-XH-8 · col B

1	B30	NP1.1	D33 → E29
2	B29	NP1.2	D35 → G29
3	B28	NP1.3	D36 → H29
4	B27	NP1.4	D10 → Q23
5	B26	NP1.5	D28 → I23
6	B25	NP1.6	D25 → L23
7	B24	NP1.7	D24 → M23
8	B23	NP1.8	D11 → P23

Solder checklist

Every wire on the board, once. 107 connections, 3006 mm of wire in total; the longest single run is 109 mm (+5V, S6.3 → J_TEENSY_B.1). Lengths are hole-to-hole Manhattan distance — the routed wire follows the grid, so that is its length, but add a few millimetres for the bend at each tip. Ticks are saved in this browser only.

colour	net	signal	from	to	mm
blue	GND		D11 S1.1	Y11 S2.1	12.7
blue	GND		Y11 S2.1	T11 S3.1	12.7
blue	GND		T11 S3.1	O11 S4.1	12.7
blue	GND		O11 S4.1	J11 S5.1	12.7
blue	GND		J11 S5.1	E11 S6.1	12.7
blue	GND		E11 S6.1	A11 TP3.1	10.2
blue	GND		A11 TP3.1	D16 B1.1	86.4
blue	GND		D16 B1.1	Z16 B2.1	10.2
blue	GND		Z16 B2.1	V16 B3.1	10.2
blue	GND		V16 B3.1	R16 B4.1	10.2
blue	GND		R16 B4.1	O16 B8.1	7.6
blue	GND		O16 B8.1	K16 B7.1	10.2
blue	GND		K16 B7.1	G16 B6.1	10.2
blue	GND		G16 B6.1	C16 B5.1	10.2
blue	GND		C16 B5.1	B23 J_TEENSY_A.1	81.3
blue	GND		B23 J_TEENSY_A.1	A29 J_TEENSY_B.2	17.8
blue	GND		A29 J_TEENSY_B.2	N29 J_TEENSY_B.15	33.0
blue	GND		N29 J_TEENSY_B.15	X35 J1.5	40.8
blue	GND		X35 J1.5	I35 J2.5	38.1
blue	GND		I35 J2.5	Z44 CB1.4	66.0
blue	GND		Z44 CB1.4	U44 CB2.4	12.7
blue	GND		U44 CB2.4	P44 CB3.4	12.7
blue	GND		P44 CB3.4	K44 CB4.4	12.7
blue	GND		K44 CB4.4	F44 CB5.4	12.7
blue	GND		F44 CB5.4	Z46 CB1.2	55.8
blue	GND		Z46 CB1.2	U46 CB2.2	12.7
blue	GND		U46 CB2.2	P46 CB3.2	12.7
blue	GND		P46 CB3.2	K46 CB4.2	12.7
blue	GND		K46 CB4.2	F46 CB5.2	12.7
red	+3V3		A10 TP4.1	D10 S1.2	73.7
red	+3V3		D10 S1.2	Y10 S2.2	12.7
red	+3V3		Y10 S2.2	T10 S3.2	12.7
red	+3V3		T10 S3.2	O10 S4.2	12.7
red	+3V3		O10 S4.2	J10 S5.2	12.7
red	+3V3		J10 S5.2	E10 S6.2	12.7
red	+3V3		E10 S6.2	M13 R12.2	27.9
red	+3V3		M13 R12.2	H13 R13.2	12.7
red	+3V3		H13 R13.2	N23 J_TEENSY_A.15	40.6
red	+3V3		N23 J_TEENSY_A.15	Z29 J_TEENSY_B.3	45.7
red	+5V		A09 TP5.1	D09 S1.3	73.7
red	+5V		D09 S1.3	Y09 S2.3	12.7
red	+5V		Y09 S2.3	T09 S3.3	12.7
red	+5V		T09 S3.3	O09 S4.3	12.7
red	+5V		O09 S4.3	J09 S5.3	12.7
red	+5V		J09 S5.3	E09 S6.3	12.7
red	+5V		E09 S6.3	B29 J_TEENSY_B.1	109.1
yellow	SDA		A08 TP1.1	D08 S1.4	73.8
yellow	SDA		D08 S1.4	Y08 S2.4	12.7
yellow	SDA		Y08 S2.4	T08 S3.4	12.7
yellow	SDA		T08 S3.4	O08 S4.4	12.7
yellow	SDA		O08 S4.4	J08 S5.4	12.7
yellow	SDA		J08 S5.4	E08 S6.4	12.7
yellow	SDA		E08 S6.4	Q13 R12.1	43.1
yellow	SDA		Q13 R12.1	T29 J_TEENSY_B.9	48.3
yellow	SCL		A07 TP2.1	D07 S1.5	73.8
yellow	SCL		D07 S1.5	Y07 S2.5	12.7
yellow	SCL		Y07 S2.5	T07 S3.5	12.7
yellow	SCL		T07 S3.5	O07 S4.5	12.7
yellow	SCL		O07 S4.5	J07 S5.5	12.7
yellow	SCL		J07 S5.5	E07 S6.5	12.7
yellow	SCL		E07 S6.5	L13 R13.1	32.9
yellow	SCL		L13 R13.1	U29 J_TEENSY_B.8	63.5
orange	D0	B1	D15 B1.2	A23 J_TEENSY_A.2	27.9
orange	D1	B2	Z15 B2.2	Z23 J_TEENSY_A.3	20.3
green	D4	B3	V15 B3.2	W23 J_TEENSY_A.6	22.8
white	D8	B4	R15 B4.2	S23 J_TEENSY_A.10	22.8
orange	D32	B5	C15 B5.2	E23 J_TEENSY_A.24	25.4
green	D30	B6	G15 B6.2	G23 J_TEENSY_A.22	20.3
green	D26	B7	K15 B7.2	K23 J_TEENSY_A.18	20.3
orange	D9	B8	O15 B8.2	R23 J_TEENSY_A.11	27.9
white	D23	CB1	Z47 CB1.1	Y29 J_TEENSY_B.4	48.3
orange	LED_ARM		Z45 CB1.3	A45 R1.1	2.6
orange	D6	CB2	U47 CB2.1	U23 J_TEENSY_A.8	61.0
white	LED_EN		U45 CB2.3	T45 R2.1	2.6
white	D14	CB3	P47 CB3.1	P29 J_TEENSY_B.13	45.7
orange	LED_SFT		P45 CB3.3	Q45 R3.1	2.6
white	D38	CB4	K47 CB4.1	J29 J_TEENSY_B.19	48.3
green	LED_CONF		K45 CB4.3	L45 R4.1	2.6
green	D34	CB5	F47 CB5.1	F29 J_TEENSY_B.23	45.7
white	LED_ALT		F45 CB5.3	E45 R5.1	2.6
orange	D22	J1.1	X39 J1.1	X29 J_TEENSY_B.5	25.4
orange	D21	J1.2	X38 J1.2	W29 J_TEENSY_B.6	25.4
orange	D20	J1.3	X37 J1.3	V29 J_TEENSY_B.7	25.5
green	D16	J1.4	X36 J1.4	R29 J_TEENSY_B.11	33.1
orange	D37	J2.1	I39 J2.1	I29 J_TEENSY_B.20	25.4
white	D39	J2.2	I38 J2.2	K29 J_TEENSY_B.18	28.0
orange	D40	J2.3	I37 J2.3	L29 J_TEENSY_B.17	28.0
green	D41	J2.4	I36 J2.4	M29 J_TEENSY_B.16	28.1
orange	D33	NP1.1	B30 NP1.1	E29 J_TEENSY_B.24	10.2
orange	D35	NP1.2	B29 NP1.2	G29 J_TEENSY_B.22	12.7
orange	D36	NP1.3	B28 NP1.3	H29 J_TEENSY_B.21	17.7
orange	D10	NP1.4	B27 NP1.4	Q23 J_TEENSY_A.12	48.4
white	D28	NP1.5	B26 NP1.5	I23 J_TEENSY_A.20	25.6
white	D25	NP1.6	B25 NP1.6	L23 J_TEENSY_A.17	30.7
green	D24	NP1.7	B24 NP1.7	M23 J_TEENSY_A.16	30.7
orange	D11	NP1.8	B23 NP1.8	P23 J_TEENSY_A.13	35.8
orange	D5	LED1	A41 R1.2	V23 J_TEENSY_A.7	58.4
orange	D17	LED2	T41 R2.2	S29 J_TEENSY_B.10	33.0
white	D15	LED3	Q41 R3.2	Q29 J_TEENSY_B.12	30.5
green	D13	LED4	L41 R4.2	O29 J_TEENSY_B.14	38.1
white	D29	LED5	E41 R5.2	H23 J_TEENSY_A.21	53.3
yellow	IRQ1		D06 S1.6	Y23 J_TEENSY_A.4	55.7
yellow	IRQ2		Y06 S2.6	X23 J_TEENSY_A.5	45.5
yellow	IRQ3		T06 S3.6	T23 J_TEENSY_A.9	43.0
yellow	IRQ4		O06 S4.6	O23 J_TEENSY_A.14	43.0
yellow	IRQ5		J06 S5.6	J23 J_TEENSY_A.19	43.0
yellow	IRQ6		E06 S6.6	F23 J_TEENSY_A.23	45.5

107 of 107 shown. On the board these 107 connections become 223 modelled jumper legs, because a run that changes both row and column is drawn as two straight legs meeting at a corner hole, and a run that would lie on top of another wire is detoured around it. Electrically each is still one connection — one length of wire, bent, will do it.

Revision notes

How this layout got here

GPIO assignment (2026-08-26). Connector signals are not in sequential blocks. Each one is wired to a Teensy pin chosen for physical proximity, solved as an assignment problem over the free GPIOs, which is why the numbers look scattered. Eighteen signals override proximity because they are already soldered and stay put: B1–B8 (D0 D1 D4 D8 / D32 D30 D26 D9), J1/J2 (D22 D21 D20 D16 / D37 D39 D40 D41, on the D13–D23 / D33–D41 rail — row 29 here) and LED4/LED5 (D13 / D29, their resistors jumpered L41→O29 and E41→H23). The other 22 — the six IRQs, the five control buttons, three of the five lamps and the eight numpad lines — moved to their nearest free pin. Firmware pin constants must follow this map (scripts/pin_map.json); the tables on this page, the schematic and the manufactured board are all generated from it.

Teensy orientation, verified against the board (2026-08-26). Two earlier revisions of this page had the module in wrong — once with the rows swapped, once with both rows reversed. It plugs in USB toward the B23/B29 end (the left edge of the header strips below), and each socket carries its Teensy row in that row's own order, neither reversed: row 23 runs GND D0 D1 … D12 +3V3 D24 … D32 left to right, row 29 runs +5V GND +3V3 D23 D22 … D13 GND D41 … D33. Three independent readings off the physical board agree: the Vin/GND/3.3V trio sits in B29 A29 Z29, B1's wire is in A23 (D0) and B2's in Z23 (D1) — exactly the firmware's pins. Every already-soldered wire keeps both its GPIO and its hole under this mapping. If this is ever doubted again, settle it by reading a hole off the board, never by checking whether the resulting map looks sensible — every table on this page is generated from the mapping, so a wrong one still looks self-consistent.

R4's jumper was moved off J1's pin (resolved). R4's LED wire had gone into L41→R29, but R29 reads D16 — J1 pin 4, already soldered. It has been pulled and re-landed five holes along in O29 (D13), so LED4 is now frozen on D13 alongside LED5's E41→H23 (H23 = D29). D13 also drives the Teensy's onboard LED, which is harmless here precisely because LED4 is a driven output — never put a pulled-up input on it.

Connector standard. S1–S6 follow the XH2.54 6-pin Haptic Console Connector Standard v1.1 — pin 1 GND, pin 2 3.3V, pin 3 5V, pin 4 SDA, pin 5 SCL, pin 6 IRQ — matching cables crimped to that spec.

Group layout. Every JST group shares one anchor row, mirrored left/right to match the physical panel (S1–S6 centred; B1–B4 mirrors B5–B8; J1 mirrors J2; CB1–CB5 near-symmetric about the centre column). Because each group shares an anchor row, the same pin number lands on the same row across the group, which is what makes the single-wire bus rails possible. Everything fits inside the physical 32×50 hole grid.

Moves since the first revision. The Teensy sockets moved one column left and two rows up (rows 25→23 and 31→29) and R12/R13 shifted two columns; S1–S6 shifted one column left to clear the TP1–TP5 header at the right edge; R1–R5 went from lying flat across row 48 to standing upright on rows 45/41 in the column beside their own CB, which is what shortened every LED-cathode jumper to one hole.

The KiCad files match this page (2026-08-26). Everything is now generated from the same scripts/pin_map.json: the perfboard has R1–R5 standing on rows 45/41 as rewired by hand (R1 A45/A41, R2 T45/T41, R3 Q45/Q41, R4 L45/L41, R5 E45/E41) with the modelled jumper legs on the back layer, the schematic's net labels carry each signal's GPIO name, and the manufactured board has been re-netted and re-routed from scratch (0 DRC violations, 0 unconnected pads) with fresh gerbers. Change a pin by editing the generator and re-running the pipeline — never by hand-editing this page or a KiCad file.