01:56:07]<gordon1> it has integrated bootloader iirc 01:56:18]<gordon1> dfu thing that triggers by BOOT0 pin 01:58:19]<L29Ah> 407? is this the only difference? 01:58:55]<gordon1> i think all of stm32f4 with usb 01:59:29]<L29Ah> oh wow 01:59:39]<L29Ah> DS tells they do 02:00:33]<L29Ah> but apparently it doesn&#39;t work 02:00:56]<L29Ah> i&#39;m holding BOOT0 and plug my shit in - get some whining about failure to establish the usb link in my dmesg 02:01:22]<L29Ah> while it works with firmware DFU 02:01:40]<gordon1> crystal most likely the reason 02:02:01]<gordon1> firmware configures PLL in the way to produce 48MHz clock required for USB 02:02:11]<gordon1> but integrated DFU bootloader is stupid 02:02:29]<gordon1> it just expects to have 8Mhz 02:04:32]<L29Ah> indeed, mine has a 25MHz crystal 02:07:51]<gordon1> Due to HSI deviation and since HSI is used to detect HSE value, the user must use low 02:07:53]<gordon1> frequency rather than high frequency HSE crystal values (low frequency values are better 02:07:56]<gordon1> detected due to larger error margin). For example, it is better to use 8 MHz instead of 02:08:01]<gordon1> 25 MHz. 02:08:27]<gordon1> page 121 02:12:07]<gordon1> basically plug and pray ... 20:22:01]<gordon1> it is a PITA yes 20:22:13]<gordon1> but ever worse with crystalless usb 20:22:21]<gordon1> i have my usb password thingy 20:22:33]<gordon1> and made a jig to program it 20:22:58]<gordon1> it depends on the position of your finger on the pcb if you&#39;re going to have it working or not 20:23:19]<gordon1> after its flashed - usb works perfectly fine 100% of the time 20:23:24]<gordon1> *it&#39;s 20:24:16]<gordon1> so yeah 20:24:22]<gordon1> try pushing on the crystal 20:24:28]<gordon1> or waving your arm around 20:24:47]<gordon1> you&#39;ll be surprised how often that does work 20:29:17]<L29Ah> OH FUCKING WOW 20:29:19]<L29Ah> gordon1: :* 20:29:31]<gordon1> lol did it work? 20:29:31]<L29Ah> i tried to be really careful when presing those boot and reset buttons 20:29:40]<L29Ah> and usb works! 20:29:45]<gordon1> yea yeah 20:29:52]<gordon1> welcome to stm32 dfu bootloader