Archived
1
0
This repo is archived. You can view files and clone it, but cannot push or open issues or pull requests.
controller/USB/pjrc/arm/usb_serial.c

249 lines
5.6 KiB
C
Raw Normal View History

#include "usb_dev.h"
#include "usb_serial.h"
#include <Lib/USBLib.h>
// defined by usb_dev.h -> usb_desc.h
#if defined(CDC_STATUS_INTERFACE) && defined(CDC_DATA_INTERFACE)
uint8_t usb_cdc_line_coding[7];
volatile uint8_t usb_cdc_line_rtsdtr=0;
volatile uint8_t usb_cdc_transmit_flush_timer=0;
static usb_packet_t *rx_packet=NULL;
static usb_packet_t *tx_packet=NULL;
static volatile uint8_t tx_noautoflush=0;
#define TRANSMIT_FLUSH_TIMEOUT 5 /* in milliseconds */
static void usb_serial_receive(void)
{
if (!usb_configuration) return;
if (rx_packet) return;
while (1) {
rx_packet = usb_rx(CDC_RX_ENDPOINT);
if (rx_packet == NULL) return;
if (rx_packet->len > 0) return;
usb_free(rx_packet);
rx_packet = NULL;
}
}
// get the next character, or -1 if nothing received
int usb_serial_getchar(void)
{
unsigned int i;
int c;
usb_serial_receive();
if (!rx_packet) return -1;
i = rx_packet->index;
c = rx_packet->buf[i++];
if (i >= rx_packet->len) {
usb_free(rx_packet);
rx_packet = NULL;
} else {
rx_packet->index = i;
}
return c;
}
// peek at the next character, or -1 if nothing received
int usb_serial_peekchar(void)
{
usb_serial_receive();
if (!rx_packet) return -1;
return rx_packet->buf[rx_packet->index];
}
// number of bytes available in the receive buffer
int usb_serial_available(void)
{
int count=0;
if (usb_configuration) {
count = usb_rx_byte_count(CDC_RX_ENDPOINT);
}
if (rx_packet) count += rx_packet->len - rx_packet->index;
return count;
}
// discard any buffered input
void usb_serial_flush_input(void)
{
usb_packet_t *rx;
if (!usb_configuration) return;
if (rx_packet) {
usb_free(rx_packet);
rx_packet = NULL;
}
while (1) {
rx = usb_rx(CDC_RX_ENDPOINT);
if (!rx) break;
usb_free(rx);
}
}
// Maximum number of transmit packets to queue so we don't starve other endpoints for memory
#define TX_PACKET_LIMIT 8
// When the PC isn't listening, how long do we wait before discarding data? If this is
// too short, we risk losing data during the stalls that are common with ordinary desktop
// software. If it's too long, we stall the user's program when no software is running.
#define TX_TIMEOUT_MSEC 70
#if F_CPU == 96000000
#define TX_TIMEOUT (TX_TIMEOUT_MSEC * 596)
#elif F_CPU == 48000000
#define TX_TIMEOUT (TX_TIMEOUT_MSEC * 428)
#elif F_CPU == 24000000
#define TX_TIMEOUT (TX_TIMEOUT_MSEC * 262)
#endif
// When we've suffered the transmit timeout, don't wait again until the computer
// begins accepting data. If no software is running to receive, we'll just discard
// data as rapidly as Serial.print() can generate it, until there's something to
// actually receive it.
static uint8_t transmit_previous_timeout=0;
// transmit a character. 0 returned on success, -1 on error
int usb_serial_putchar(uint8_t c)
{
#if 1
return usb_serial_write(&c, 1);
#endif
#if 0
uint32_t wait_count;
tx_noautoflush = 1;
if (!tx_packet) {
wait_count = 0;
while (1) {
if (!usb_configuration) {
tx_noautoflush = 0;
return -1;
}
if (usb_tx_packet_count(CDC_TX_ENDPOINT) < TX_PACKET_LIMIT) {
tx_noautoflush = 1;
tx_packet = usb_malloc();
if (tx_packet) break;
tx_noautoflush = 0;
}
if (++wait_count > TX_TIMEOUT || transmit_previous_timeout) {
transmit_previous_timeout = 1;
return -1;
}
}
}
transmit_previous_timeout = 0;
tx_packet->buf[tx_packet->index++] = c;
if (tx_packet->index < CDC_TX_SIZE) {
usb_cdc_transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT;
} else {
tx_packet->len = CDC_TX_SIZE;
usb_cdc_transmit_flush_timer = 0;
usb_tx(CDC_TX_ENDPOINT, tx_packet);
tx_packet = NULL;
}
tx_noautoflush = 0;
return 0;
#endif
}
int usb_serial_write(const void *buffer, uint32_t size)
{
#if 1
uint32_t len;
uint32_t wait_count;
const uint8_t *src = (const uint8_t *)buffer;
uint8_t *dest;
tx_noautoflush = 1;
while (size > 0) {
if (!tx_packet) {
wait_count = 0;
while (1) {
if (!usb_configuration) {
tx_noautoflush = 0;
return -1;
}
if (usb_tx_packet_count(CDC_TX_ENDPOINT) < TX_PACKET_LIMIT) {
tx_noautoflush = 1;
tx_packet = usb_malloc();
if (tx_packet) break;
tx_noautoflush = 0;
}
if (++wait_count > TX_TIMEOUT || transmit_previous_timeout) {
transmit_previous_timeout = 1;
return -1;
}
yield();
}
}
transmit_previous_timeout = 0;
len = CDC_TX_SIZE - tx_packet->index;
if (len > size) len = size;
dest = tx_packet->buf + tx_packet->index;
tx_packet->index += len;
size -= len;
while (len-- > 0) *dest++ = *src++;
if (tx_packet->index < CDC_TX_SIZE) {
usb_cdc_transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT;
} else {
tx_packet->len = CDC_TX_SIZE;
usb_cdc_transmit_flush_timer = 0;
usb_tx(CDC_TX_ENDPOINT, tx_packet);
tx_packet = NULL;
}
}
tx_noautoflush = 0;
return 0;
#endif
#if 0
const uint8_t *p = (const uint8_t *)buffer;
int r;
while (size) {
r = usb_serial_putchar(*p++);
if (r < 0) return -1;
size--;
}
return 0;
#endif
}
void usb_serial_flush_output(void)
{
if (!usb_configuration) return;
//serial_print("usb_serial_flush_output\n");
if (tx_packet && tx_packet->index > 0) {
usb_cdc_transmit_flush_timer = 0;
tx_packet->len = tx_packet->index;
usb_tx(CDC_TX_ENDPOINT, tx_packet);
tx_packet = NULL;
}
// while (usb_tx_byte_count(CDC_TX_ENDPOINT) > 0) ; // wait
}
void usb_serial_flush_callback(void)
{
if (tx_noautoflush) return;
//serial_print("usb_flush_callback \n");
tx_packet->len = tx_packet->index;
usb_tx(CDC_TX_ENDPOINT, tx_packet);
tx_packet = NULL;
//serial_print("usb_flush_callback end\n");
}
#endif // CDC_STATUS_INTERFACE && CDC_DATA_INTERFACE