From e581daec90bb50d7f1594e099bd60d28273eab1e Mon Sep 17 00:00:00 2001 From: R Date: Tue, 23 Apr 2024 16:17:41 +0100 Subject: [PATCH] another gotcha --- README.md | 1 + 1 file changed, 1 insertion(+) diff --git a/README.md b/README.md index 6b16742..fa39b37 100644 --- a/README.md +++ b/README.md @@ -9,6 +9,7 @@ - Code size is improved through use of "XW" instructions, which are not upstream - Supports USBD peripheral *only* (i.e. not USBFS) - USBD and USBFS are completely different, and the QFN28 package (which is available in largest quantities on LCSC) only bonds out USBD + - Note that USBD requires a USB A-A cable if using the official devkit - Runs off of internal 8 MHz oscillator (despite stability concerns) - The HSI oscillator's tolerance (-1.0% to +1.6%) is well outside of the range specified for USB full speed ($\pm$ 0.25%), but it seems to work in practice n=1 ¯\\\_(ツ)\_/¯ - Should work across most of the CH32V2xx and CH32V3xx family with appropriate changes to hardcoded constants.