/* Teensyduino Core Library * http://www.pjrc.com/teensy/ * Copyright (c) 2013 PJRC.COM, LLC. * Modified by Jacob Alexander 2013-2016 * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * 1. The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * 2. If the Software is incorporated into a build system that allows * selection among a list of target devices, then similar target * devices manufactured by PJRC.COM must be included in the list of * target devices and selectable in the same manner. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include #if enableVirtualSerialPort_define == 1 // ----- Includes ----- // Compiler Includes #include // For memcpy // Project Includes #include // Local Includes #include "usb_dev.h" #include "usb_serial.h" // ----- Defines ----- #define TRANSMIT_FLUSH_TIMEOUT 5 /* in milliseconds */ // 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 == 72000000 #define TX_TIMEOUT (TX_TIMEOUT_MSEC * 512) // XXX Correct? #elif F_CPU == 48000000 #define TX_TIMEOUT (TX_TIMEOUT_MSEC * 428) #elif F_CPU == 24000000 #define TX_TIMEOUT (TX_TIMEOUT_MSEC * 262) #endif // ----- Variables ----- // Serial port settings (baud rate, control signals, etc) set by the host // These are *ignored*, except to return back to the host if requested volatile USBCDCLineCoding usb_cdc_line_coding = { 115200, 0, 0, 8, }; 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; // 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; // ----- Functions ----- // get the next character, or -1 if nothing received int usb_serial_getchar() { unsigned int i; int c; if ( !rx_packet ) { if ( !usb_configuration ) return -1; rx_packet = usb_rx( CDC_RX_ENDPOINT ); 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() { if ( !rx_packet ) { if ( !usb_configuration ) return -1; rx_packet = usb_rx( CDC_RX_ENDPOINT ); if ( !rx_packet ) return -1; } if ( !rx_packet ) return -1; return rx_packet->buf[ rx_packet->index ]; } // number of bytes available in the receive buffer int usb_serial_available() { int count = usb_rx_byte_count( CDC_RX_ENDPOINT ); if ( rx_packet ) count += rx_packet->len - rx_packet->index; return count; } // read a block of bytes to a buffer int usb_serial_read( void *buffer, uint32_t size ) { uint8_t *p = (uint8_t *)buffer; uint32_t qty, count=0; while ( size ) { if ( !usb_configuration ) break; if ( !rx_packet ) { rx: rx_packet = usb_rx(CDC_RX_ENDPOINT); if ( !rx_packet ) break; if ( rx_packet->len == 0 ) { usb_free(rx_packet); goto rx; } } qty = rx_packet->len - rx_packet->index; if ( qty > size ) qty = size; memcpy( p, rx_packet->buf + rx_packet->index, qty ); p += qty; count += qty; size -= qty; rx_packet->index += qty; if ( rx_packet->index >= rx_packet->len ) { usb_free( rx_packet ); rx_packet = NULL; } } return count; } // discard any buffered input void usb_serial_flush_input() { 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 ); } } // transmit a character. 0 returned on success, -1 on error int usb_serial_putchar( uint8_t c ) { return usb_serial_write( &c, 1 ); } int usb_serial_write( const void *buffer, uint32_t size ) { 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 ) { tx_packet->len = CDC_TX_SIZE; usb_tx( CDC_TX_ENDPOINT, tx_packet ); tx_packet = NULL; } usb_cdc_transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT; } tx_noautoflush = 0; return 0; } void usb_serial_flush_output() { if ( !usb_configuration ) return; tx_noautoflush = 1; if ( tx_packet ) { usb_cdc_transmit_flush_timer = 0; tx_packet->len = tx_packet->index; usb_tx( CDC_TX_ENDPOINT, tx_packet ); tx_packet = NULL; } else { usb_packet_t *tx = usb_malloc(); if ( tx ) { usb_cdc_transmit_flush_timer = 0; usb_tx( CDC_TX_ENDPOINT, tx ); } else { usb_cdc_transmit_flush_timer = 1; } } tx_noautoflush = 0; } void usb_serial_flush_callback() { if ( tx_noautoflush ) return; if ( tx_packet ) { tx_packet->len = tx_packet->index; usb_tx( CDC_TX_ENDPOINT, tx_packet ); tx_packet = NULL; } else { usb_packet_t *tx = usb_malloc(); if ( tx ) { usb_tx( CDC_TX_ENDPOINT, tx ); } else { usb_cdc_transmit_flush_timer = 1; } } } #endif