Acorn tests and their wires on a Raspberry Pi 5

The tests of the Acorn check on a Raspberry Pi 5: the wires each test uses, and what a pass shows.

Which test uses which wire

Test	Wires it uses	A pass shows	Runs on a card still on SQRL’s image
pcie-link	the M.2 slot	the card is seated and the PCIe link is at the setup’s speed and width	yes
jtag	P1: TCK, TMS, TDO for the IDCODE read; TDI as well for the device DNA read	all four JTAG wires, and that the FPGA is the variant’s part	yes
pcie-bar0	the M.2 slot	the fpgas.online design is running and answers over PCIe	no: the board gets fault: unconverted: …; this test, p2-uart, p2-serial, p2-gpio, flash, ddr and scratch are listed as not run (pcie-link, jtag and rp1-pio still run)
p2-uart	P2: K2 (FPGA transmit) to the Pi’s RXD (GPIO15), J2 (FPGA receive) from the Pi’s TXD (GPIO14)	the serial pair, in the right direction	no
p2-serial	the same two wires, driven and read as plain pins in both directions	each of J2 and K2 on its own, so a crossed pair or one open wire is told apart	no
p2-gpio	P2: J5 to GPIO3, H5 to GPIO4, in both directions	the two spare wires	no
rp1-pio	no wire: /dev/pio0 on a Pi 5 or CM5	nothing about the wiring (not run on other hosts)	yes
flash, ddr, scratch	no wire of the cable, except that scratch also goes over the serial pair	nothing about the wiring	no

On a card that has not been converted, pcie-link and jtag are the wiring tests. The P2 wires are tested once the card runs the fpgas.online design (How to install the fpgas.online images on an Acorn).