From 7c7c7b161df5be99aee9dea444b6e4beacf78438 Mon Sep 17 00:00:00 2001 From: Damien George Date: Fri, 13 Oct 2017 12:00:47 +1100 Subject: [PATCH] stm32/usbd_cdc_interface: Don't reset CDC output buf on initialisation. So that characters can be buffered before the USB device is connected (restoring behviour of the driver before recent state refactoring). --- ports/stm32/usbd_cdc_interface.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/ports/stm32/usbd_cdc_interface.c b/ports/stm32/usbd_cdc_interface.c index 4c49c9321f..2e9fba917c 100644 --- a/ports/stm32/usbd_cdc_interface.c +++ b/ports/stm32/usbd_cdc_interface.c @@ -57,10 +57,14 @@ #define CDC_SEND_BREAK 0x23 uint8_t *usbd_cdc_init(usbd_cdc_itf_t *cdc, usbd_cdc_msc_hid_state_t *usbd) { + // Link the parent state cdc->usbd = usbd; + + // Reset all the CDC state + // Note: we don't reset tx_buf_ptr_in in order to allow the output buffer to + // be filled (by usbd_cdc_tx_always) before the USB device is connected. cdc->rx_buf_put = 0; cdc->rx_buf_get = 0; - cdc->tx_buf_ptr_in = 0; cdc->tx_buf_ptr_out = 0; cdc->tx_buf_ptr_out_shadow = 0; cdc->tx_buf_ptr_wait_count = 0;