; The reference loom for a LattePanda IOTA tower: RP2040 -> one TMC5160-BOB.
; AS BUILT on tower 10.11.12.121, transcribed 2026-09-15. Not the map proposed
; in docs/hardware-porting-plan.md section 2 - that one was never wired.
;
;   IOTA   Function          TMC5160-BOB
;   3.3V   logic supply      pin 1  VCC_IO  (3.3 V: the RP2040 is NOT 5 V tolerant)
;   GND    signal ground     pin 2  GND
;   GP1    SPI chip select   pin 3  CSN
;   GP2    SPI clock         pin 4  SCK
;   GP3    SPI MOSI          pin 5  SDI
;   GP0    SPI MISO          pin 6  SDO
;   GP4    driver enable     pin 9  DRV_ENN
;
; The SPI pins are not a free choice. The firmware drives SPI0, which reaches
; SCK {2,6,18,22}, MOSI {3,7,19,23}, MISO {0,4,16,20} and nothing else;
; firmware/tools/gen_wiring.py refuses anything outside those at build time.
; GP1 is SPI0's hardware CSn, though the driver toggles it in software anyway.
;
; The installer copies this block into hardware.ini when the tower is wired to
; this loom. A tower wired differently gets its own numbers - and the comments
; beside them should then say what each wire really goes to.
[Pins]
spi_sck  = 2      ; -> BOB pin 4 SCK
spi_mosi = 3      ; -> BOB pin 5 SDI
spi_miso = 0      ; -> BOB pin 6 SDO
yaw_cs   = 1      ; -> BOB pin 3 CSN
yaw_en   = 4      ; -> BOB pin 9 DRV_ENN