Changes for version 3.1804 - 2026-07-13
- Fixed phys_to_gpio() and wpi_to_gpio(): they forwarded out-of-range / non-integer input straight to the wiringPi library lookups (64-entry tables), an out-of-bounds read; they now guard the index and return the -1 "no such pin" sentinel, matching phys_to_wpi()
- Added t/91-spi_data.t (spi_data channel/arrayref/len + spiDataRW byte-range croaks), t/92-pin_map_bounds.t (the phys/wpi_to_gpio bounds guard above), t/93-arg_validation.t (shift_reg_setup/serial_gets/ lcd_init argument croaks), and t/94-bmp180_math.t (the bmp180_temp/ pressure unit conversions, via stubbed reads) - all HW-free
- Added pcf8574Setup(pin_base, i2c_address) (exported, from libwiringPi): registers a PCF8574 I2C I/O-expander's 8 pins as virtual GPIOs, so the existing lcd*()/digital_* functions can drive an HD44780 over an I2C backpack by routing their digitalWrite() calls to the expander. Used by RPi::WiringPi's lcd(i2c => ...) path
- Makefile.PL's minimum wiringPi version now comes from RPi::Const's WIRINGPI_MIN_VERSION (literal 3.18 fallback when RPi::Const isn't installed at configure time); RPi::Const prereq bumped to 1.07; DESCRIPTION POD points at the canonical constant
- Added spiNoCS(channel, state) / spi_no_cs(): sets or clears the kernel SPI_NO_CS flag on an open SPI channel so transactions can be framed by a user-managed GPIO chip select without the hardware CE0/CE1 pin strobing alongside (used by RPi::SPI's GPIO CS mode)
- Added spiBitBang(clk, mosi, miso, cs, data, len, mode, delay_us) / spi_bit_bang(): full software SPI transaction on arbitrary GPIO pins (modes 0-3, MSB-first, active-low CS, optional per-phase delay) with no kernel SPI involvement; the frame loop runs entirely in C. Used by RPi::SPI's new bit-bang mode
- Added t/95-spi_no_cs.t and t/96-spi_bit_bang.t (HW-free validation croaks for the two new functions)
- Added t/78-background_interrupt_single.t: HW-free coverage of the singular background_interrupt() - its pre-fork argument validation croaks, and the opt-in results channel (B5) round-trip (a real fork with set_interrupt()/wait_interrupts() stubbed, so the child frames a return value up the pipe and the parent handle's read() drains it), plus the no-results-channel fh()/read() undef case
- Extended t/75-interrupts.t: auto_dispatch_interrupts() now also verifies that a pre-existing handler on the chosen signal is saved on enable and restored (not deleted) on disable
- Removed a stale INT.md entry from MANIFEST (the file never existed; the interrupt doc is docs/interrupt-examples.md) - it was failing the manicheck / would break make dist
- Makefile.PL: replaced the inline wiringPi presence/version guard with a shim calling RPi::Const::BuildCheck::wiringpi_build_check(), pulled in via CONFIGURE_REQUIRES => { 'RPi::Const' => 1.07 }; dropped "use version". The check (and the canonical 3.18 minimum) now lives in one place for the whole RPi:: family, and the buggy decimal version compare / silent-pass-on-unparseable-gpio are gone. Falls back to an NA-safe exit-0 message if RPi::Const isn't yet installed
Documentation
Interrupt (ISR) usage examples
Concurrency & background-worker examples
Modules
API for wiringPi, providing access to the Raspberry Pi's board, GPIO and connected peripherals
Handle for a single-pin background interrupt child
Handle for a shared multi-pin background interrupt child
Handle for a fork-based background worker
Handle for an ithread-based background worker