Muhammad Bilal Awan

Hi all, I’ve designed and built a custom H616 board using the Orange Pi Zero 2W schematic as a reference, but with an AP6212 for Wi-Fi/BT. The board boots the Orange Pi Zero 2W image to a login prompt, with DRAM, HDMI and UART working, but the AP6212 never appears on SDIO. The AP6212 section of the schematic is attached. Setup SoC: Allwinner H616 Wi-Fi/BT: AP6212 on SDC1 (4021000.mmc) WL_REG_ON: PG18 OS: Orange Pi OS (Arch), Zero 2W image with a custom DTB brcmfmac, the Broadcom firmware and the AP6212 NVRAM are present on the image What I’ve tried mmc-pwrseq with ext_clock mmc-pwrseq without a clock Holding WL_REG_ON high with a regulator-fixed on PG18 With WL_REG_ON confirmed high, the SDIO scan still times out and the module doesn’t enumerate. Measurements VBAT: [value] VDDIO: [value] SDC1 I/O voltage: [value] WL_REG_ON timing relative to VBAT/VDDIO: [details] LPO (32.768 kHz) at the module pin: [frequency / amplitude / not present] CLK activity on SDC1 during the scan: [yes/no, frequency] Other details that may matter The kernel has no RTC 32 kHz clock provider (SUN6I_RTC_CCU=m), so the LPO may not be running. The image was built for a UWE5622, so it also ships those Unisoc drivers. I see a kernel oops about 57 s into boot, possibly from those drivers. I can’t yet say whether it’s related. Where I’d appreciate feedback Do you see any mistakes in the AP6212 power, VDDIO, LPO, crystal or SDIO connections, including pull-ups? Will the AP6212 enumerate at all without a valid 32.768 kHz LPO? Is there anything specific to moving from the Zero 2W’s Wi-Fi module to an AP6212 that I may have missed? If you’ve brought up an AP6212 or similar Broadcom module on Allwinner, what turned out to be the problem? Thanks for taking a look. I’m happy to share more of the schematic or run any measurements that would help.