The board and its pin map

board.h names every pin the motherboard uses, so drivers and apps say board::pin::kSatTx rather than seed::D2. It is plain constants with no libDaisy in it, so host tests include it too, and they check the map against libDaisy’s own pin table: a typo in a port or pin number fails a test instead of driving the wrong pin. The hardware it describes is hardware/rodeo-motherboard/docs/rev-b.md. Every name and value is in the API reference.

Every pin is spoken for

Seed pin	libDaisy	Use	board::pin::
1	D0	Expansion header chip-select	kSpiExtCs
2, 3	D1, D2	Satellite chain RX, TX (USART3)	kSatRx, kSatTx
4	D3	Second codec reset	kCodec2Reset
5–7	D4–D6	microSD, 1-bit	kSdD0, kSdCmd, kSdClk
8	D7	I/O connector D1	kIo[kIoD1]
9–11	D8–D10	SPI1 to the expansion header	kSpiSck, kSpiMiso, kSpiMosi
12, 13	D11, D12	I²C1: OLED, battery gauge, four taps	kI2cScl, kI2cSda
14, 15	D13, D14	MIDI (USART1)	kMidiTx, kMidiRx
22–28	D15–D21	I/O connectors A1–A7	kIo[kIoA1]…
29, 30	D22, D23	I/O connectors CV2, CV1	kIo[kIoCv2], kIo[kIoCv1]
31–35	D24–D28	Second codec, SAI2	kCodec2Mclk…
36, 37	D29, D30	USB to the power board	kUsbDm, kUsbDp

The I/O connectors

Ten 3-pin connectors — ground, the signal through 1 kΩ, and 3.3 V — named by their silkscreen and listed in that order in board::kIo:

Silkscreen	Can do	adc	dac
D1	Digital in or out	—	—
A1–A7	Digital, or analog in	seed::A0–A6	—
CV1	DAC out (0–3.3 V), or analog in	seed::A8	1
CV2	DAC out (0–3.3 V), or analog in	seed::A7	2

Two pairs share an external-interrupt line, so only one connector of each pair can be an interrupt input: A3 and A6 (PB1, PC1), and A7 and CV1 (PC4, PA4). board::SharesExti() answers it for any two pins, and a host test fails if the map ever grows another pair.

From board.h to libDaisy

board.h stays host-safe, so the conversion lives in board_daisy.h, which only target code includes:

#include "board_daisy.h"

GPIO gate;
gate.Init(board::ToDaisy(board::kIo[board::kIoD1].pin), GPIO::Mode::INPUT);

Also in board.h

• I²C addresses: the OLED at 0x3C, the MAX17048 battery gauge at 0x36.
• Audio: four in, four out at 48 kHz. Channels 1/2 are the Seed’s own codec, 3/4 the CS4272, as on the back panel. The block size is 48 samples, one per millisecond, so a USB audio frame is exactly one block.