3333#include "samd_soc.h"
3434#include "tusb.h"
3535
36- #if MICROPY_KBD_EXCEPTION
37- int mp_interrupt_char = -1 ;
38-
39- void tud_cdc_rx_wanted_cb (uint8_t itf , char wanted_char ) {
40- (void )itf ;
41- (void )wanted_char ;
42- tud_cdc_read_char (); // discard interrupt char
43- mp_sched_keyboard_interrupt ();
44- }
36+ #ifndef MICROPY_HW_STDIN_BUFFER_LEN
37+ #define MICROPY_HW_STDIN_BUFFER_LEN 128
38+ #endif
39+
40+ STATIC uint8_t stdin_ringbuf_array [MICROPY_HW_STDIN_BUFFER_LEN ];
41+ ringbuf_t stdin_ringbuf = { stdin_ringbuf_array , sizeof (stdin_ringbuf_array ), 0 , 0 };
4542
46- void mp_hal_set_interrupt_char (int c ) {
47- mp_interrupt_char = c ;
48- tud_cdc_set_wanted_char (c );
43+ uint8_t cdc_itf_pending ; // keep track of cdc interfaces which need attention to poll
44+
45+ void poll_cdc_interfaces (void ) {
46+ // any CDC interfaces left to poll?
47+ if (cdc_itf_pending && ringbuf_free (& stdin_ringbuf )) {
48+ for (uint8_t itf = 0 ; itf < 8 ; ++ itf ) {
49+ if (cdc_itf_pending & (1 << itf )) {
50+ tud_cdc_rx_cb (itf );
51+ if (!cdc_itf_pending ) {
52+ break ;
53+ }
54+ }
55+ }
56+ }
4957}
5058
51- #endif
59+ void tud_cdc_rx_cb (uint8_t itf ) {
60+ // consume pending USB data immediately to free usb buffer and keep the endpoint from stalling.
61+ // in case the ringbuffer is full, mark the CDC interface that need attention later on for polling
62+ cdc_itf_pending &= ~(1 << itf );
63+ for (uint32_t bytes_avail = tud_cdc_n_available (itf ); bytes_avail > 0 ; -- bytes_avail ) {
64+ if (ringbuf_free (& stdin_ringbuf )) {
65+ int data_char = tud_cdc_read_char ();
66+ #if MICROPY_KBD_EXCEPTION
67+ if (data_char == mp_interrupt_char ) {
68+ // Clear the ring buffer
69+ stdin_ringbuf .iget = stdin_ringbuf .iput = 0 ;
70+ // and stop
71+ mp_sched_keyboard_interrupt ();
72+ } else {
73+ ringbuf_put (& stdin_ringbuf , data_char );
74+ }
75+ #else
76+ ringbuf_put (& stdin_ringbuf , data_char );
77+ #endif
78+ } else {
79+ cdc_itf_pending |= (1 << itf );
80+ return ;
81+ }
82+ }
83+ }
5284
5385void mp_hal_set_pin_mux (mp_hal_pin_obj_t pin , uint8_t mux ) {
5486 int pin_grp = pin / 32 ;
@@ -90,9 +122,12 @@ void mp_hal_delay_us(mp_uint_t us) {
90122
91123uintptr_t mp_hal_stdio_poll (uintptr_t poll_flags ) {
92124 uintptr_t ret = 0 ;
93- if (tud_cdc_connected () && tud_cdc_available ()) {
125+
126+ poll_cdc_interfaces ();
127+ if ((poll_flags & MP_STREAM_POLL_RD ) && ringbuf_peek (& stdin_ringbuf ) != -1 ) {
94128 ret |= MP_STREAM_POLL_RD ;
95129 }
130+
96131 #if MICROPY_PY_OS_DUPTERM
97132 ret |= mp_uos_dupterm_poll (poll_flags );
98133 #endif
@@ -101,13 +136,13 @@ uintptr_t mp_hal_stdio_poll(uintptr_t poll_flags) {
101136
102137int mp_hal_stdin_rx_chr (void ) {
103138 for (;;) {
104- if (tud_cdc_connected () && tud_cdc_available ()) {
105- uint8_t buf [1 ];
106- uint32_t count = tud_cdc_read (buf , sizeof (buf ));
107- if (count ) {
108- return buf [0 ];
109- }
139+
140+ poll_cdc_interfaces ();
141+ int c = ringbuf_get (& stdin_ringbuf );
142+ if (c != -1 ) {
143+ return c ;
110144 }
145+
111146 #if MICROPY_PY_OS_DUPTERM
112147 int dupterm_c = mp_uos_dupterm_rx_chr ();
113148 if (dupterm_c >= 0 ) {
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