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Diffstat (limited to 'usb_serial.c')
| -rw-r--r-- | usb_serial.c | 940 |
1 files changed, 940 insertions, 0 deletions
diff --git a/usb_serial.c b/usb_serial.c new file mode 100644 index 0000000..7d83076 --- /dev/null +++ b/usb_serial.c @@ -0,0 +1,940 @@ +/* USB Serial Example for Teensy USB Development Board + * http://www.pjrc.com/teensy/usb_serial.html + * Copyright (c) 2008,2010,2011 PJRC.COM, LLC + * + * 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: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * 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. + */ + +// Version 1.0: Initial Release +// Version 1.1: support Teensy++ +// Version 1.2: fixed usb_serial_available +// Version 1.3: added transmit bandwidth test +// Version 1.4: added usb_serial_write +// Version 1.5: add support for Teensy 2.0 +// Version 1.6: fix zero length packet bug +// Version 1.7: fix usb_serial_set_control + +#include "project.h" + +#define USB_SERIAL_PRIVATE_INCLUDE +#include "usb_serial.h" + + +/************************************************************************** + * + * Configurable Options + * + **************************************************************************/ + +// You can change these to give your code its own name. On Windows, +// these are only used before an INF file (driver install) is loaded. +#define STR_MANUFACTURER L"Me" +#define STR_PRODUCT L"Clock" + +// All USB serial devices are supposed to have a serial number +// (according to Microsoft). On windows, a new COM port is created +// for every unique serial/vendor/product number combination. If +// you program 2 identical boards with 2 different serial numbers +// and they are assigned COM7 and COM8, each will always get the +// same COM port number because Windows remembers serial numbers. +// +// On Mac OS-X, a device file is created automatically which +// incorperates the serial number, eg, /dev/cu-usbmodem12341 +// +// Linux by default ignores the serial number, and creates device +// files named /dev/ttyACM0, /dev/ttyACM1... in the order connected. +// Udev rules (in /etc/udev/rules.d) can define persistent device +// names linked to this serial number, as well as permissions, owner +// and group settings. +#define STR_SERIAL_NUMBER L"12345" + +// Mac OS-X and Linux automatically load the correct drivers. On +// Windows, even though the driver is supplied by Microsoft, an +// INF file is needed to load the driver. These numbers need to +// match the INF file. +#define VENDOR_ID 0x16C0 +#define PRODUCT_ID 0x047A + +// When you write data, it goes into a USB endpoint buffer, which +// is transmitted to the PC when it becomes full, or after a timeout +// with no more writes. Even if you write in exactly packet-size +// increments, this timeout is used to send a "zero length packet" +// that tells the PC no more data is expected and it should pass +// any buffered data to the application that may be waiting. If +// you want data sent immediately, call usb_serial_flush_output(). +#define TRANSMIT_FLUSH_TIMEOUT 5 /* in milliseconds */ + +// If the PC is connected but not "listening", this is the length +// of time before usb_serial_getchar() returns with an error. This +// is roughly equivilant to a real UART simply transmitting the +// bits on a wire where nobody is listening, except you get an error +// code which you can ignore for serial-like discard of data, or +// use to know your data wasn't sent. +#define TRANSMIT_TIMEOUT 25 /* in milliseconds */ + +// USB devices are supposed to implment a halt feature, which is +// rarely (if ever) used. If you comment this line out, the halt +// code will be removed, saving 116 bytes of space (gcc 4.3.0). +// This is not strictly USB compliant, but works with all major +// operating systems. +#define SUPPORT_ENDPOINT_HALT + + + +/************************************************************************** + * + * Endpoint Buffer Configuration + * + **************************************************************************/ + +// These buffer sizes are best for most applications, but perhaps if you +// want more buffering on some endpoint at the expense of others, this +// is where you can make such changes. The AT90USB162 has only 176 bytes +// of DPRAM (USB buffers) and only endpoints 3 & 4 can double buffer. + +#define ENDPOINT0_SIZE 16 +#define CDC_ACM_ENDPOINT 2 +#define CDC_RX_ENDPOINT 3 +#define CDC_TX_ENDPOINT 4 +#if defined(__AVR_AT90USB162__) +#define CDC_ACM_SIZE 16 +#define CDC_ACM_BUFFER EP_SINGLE_BUFFER +#define CDC_RX_SIZE 32 +#define CDC_RX_BUFFER EP_DOUBLE_BUFFER +#define CDC_TX_SIZE 32 +#define CDC_TX_BUFFER EP_DOUBLE_BUFFER +#else +#define CDC_ACM_SIZE 16 +#define CDC_ACM_BUFFER EP_SINGLE_BUFFER +#define CDC_RX_SIZE 64 +#define CDC_RX_BUFFER EP_DOUBLE_BUFFER +#define CDC_TX_SIZE 64 +#define CDC_TX_BUFFER EP_DOUBLE_BUFFER +#endif + +static const uint8_t PROGMEM endpoint_config_table[] = { + 0, + 1, EP_TYPE_INTERRUPT_IN, EP_SIZE(CDC_ACM_SIZE) | CDC_ACM_BUFFER, + 1, EP_TYPE_BULK_OUT, EP_SIZE(CDC_RX_SIZE) | CDC_RX_BUFFER, + 1, EP_TYPE_BULK_IN, EP_SIZE(CDC_TX_SIZE) | CDC_TX_BUFFER +}; + + +/************************************************************************** + * + * Descriptor Data + * + **************************************************************************/ + +// Descriptors are the data that your computer reads when it auto-detects +// this USB device (called "enumeration" in USB lingo). The most commonly +// changed items are editable at the top of this file. Changing things +// in here should only be done by those who've read chapter 9 of the USB +// spec and relevant portions of any USB class specifications! + +const static uint8_t PROGMEM device_descriptor[] = { + 18, // bLength + 1, // bDescriptorType + 0x00, 0x02, // bcdUSB + 2, // bDeviceClass + 0, // bDeviceSubClass + 0, // bDeviceProtocol + ENDPOINT0_SIZE, // bMaxPacketSize0 + LSB(VENDOR_ID), MSB(VENDOR_ID), // idVendor + LSB(PRODUCT_ID), MSB(PRODUCT_ID), // idProduct + 0x00, 0x01, // bcdDevice + 1, // iManufacturer + 2, // iProduct + 3, // iSerialNumber + 1 // bNumConfigurations +}; + +#define CONFIG1_DESC_SIZE (9+9+5+5+4+5+7+9+7+7) +const static uint8_t PROGMEM config1_descriptor[CONFIG1_DESC_SIZE] = { + // configuration descriptor, USB spec 9.6.3, page 264-266, Table 9-10 + 9, // bLength; + 2, // bDescriptorType; + LSB(CONFIG1_DESC_SIZE), // wTotalLength + MSB(CONFIG1_DESC_SIZE), + 2, // bNumInterfaces + 1, // bConfigurationValue + 0, // iConfiguration + 0xC0, // bmAttributes + 50, // bMaxPower + // interface descriptor, USB spec 9.6.5, page 267-269, Table 9-12 + 9, // bLength + 4, // bDescriptorType + 0, // bInterfaceNumber + 0, // bAlternateSetting + 1, // bNumEndpoints + 0x02, // bInterfaceClass + 0x02, // bInterfaceSubClass + 0x01, // bInterfaceProtocol + 0, // iInterface + // CDC Header Functional Descriptor, CDC Spec 5.2.3.1, Table 26 + 5, // bFunctionLength + 0x24, // bDescriptorType + 0x00, // bDescriptorSubtype + 0x10, 0x01, // bcdCDC + // Call Management Functional Descriptor, CDC Spec 5.2.3.2, Table 27 + 5, // bFunctionLength + 0x24, // bDescriptorType + 0x01, // bDescriptorSubtype + 0x01, // bmCapabilities + 1, // bDataInterface + // Abstract Control Management Functional Descriptor, CDC Spec 5.2.3.3, Table 28 + 4, // bFunctionLength + 0x24, // bDescriptorType + 0x02, // bDescriptorSubtype + 0x06, // bmCapabilities + // Union Functional Descriptor, CDC Spec 5.2.3.8, Table 33 + 5, // bFunctionLength + 0x24, // bDescriptorType + 0x06, // bDescriptorSubtype + 0, // bMasterInterface + 1, // bSlaveInterface0 + // endpoint descriptor, USB spec 9.6.6, page 269-271, Table 9-13 + 7, // bLength + 5, // bDescriptorType + CDC_ACM_ENDPOINT | 0x80, // bEndpointAddress + 0x03, // bmAttributes (0x03=intr) + CDC_ACM_SIZE, 0, // wMaxPacketSize + 64, // bInterval + // interface descriptor, USB spec 9.6.5, page 267-269, Table 9-12 + 9, // bLength + 4, // bDescriptorType + 1, // bInterfaceNumber + 0, // bAlternateSetting + 2, // bNumEndpoints + 0x0A, // bInterfaceClass + 0x00, // bInterfaceSubClass + 0x00, // bInterfaceProtocol + 0, // iInterface + // endpoint descriptor, USB spec 9.6.6, page 269-271, Table 9-13 + 7, // bLength + 5, // bDescriptorType + CDC_RX_ENDPOINT, // bEndpointAddress + 0x02, // bmAttributes (0x02=bulk) + CDC_RX_SIZE, 0, // wMaxPacketSize + 0, // bInterval + // endpoint descriptor, USB spec 9.6.6, page 269-271, Table 9-13 + 7, // bLength + 5, // bDescriptorType + CDC_TX_ENDPOINT | 0x80, // bEndpointAddress + 0x02, // bmAttributes (0x02=bulk) + CDC_TX_SIZE, 0, // wMaxPacketSize + 0 // bInterval +}; + +// If you're desperate for a little extra code memory, these strings +// can be completely removed if iManufacturer, iProduct, iSerialNumber +// in the device desciptor are changed to zeros. +struct usb_string_descriptor_struct { + uint8_t bLength; + uint8_t bDescriptorType; + int16_t wString[]; +}; +const static struct usb_string_descriptor_struct PROGMEM string0 = { + 4, + 3, + {0x0409} +}; +const static struct usb_string_descriptor_struct PROGMEM string1 = { + sizeof(STR_MANUFACTURER), + 3, + STR_MANUFACTURER +}; +const static struct usb_string_descriptor_struct PROGMEM string2 = { + sizeof(STR_PRODUCT), + 3, + STR_PRODUCT +}; +const static struct usb_string_descriptor_struct PROGMEM string3 = { + sizeof(STR_SERIAL_NUMBER), + 3, + STR_SERIAL_NUMBER +}; + +// This table defines which descriptor data is sent for each specific +// request from the host (in wValue and wIndex). +const static struct descriptor_list_struct { + uint16_t wValue; + uint16_t wIndex; + const uint8_t *addr; + uint8_t length; +} PROGMEM descriptor_list[] = { + {0x0100, 0x0000, device_descriptor, sizeof(device_descriptor)}, + {0x0200, 0x0000, config1_descriptor, sizeof(config1_descriptor)}, + {0x0300, 0x0000, (const uint8_t *)&string0, 4}, + {0x0301, 0x0409, (const uint8_t *)&string1, sizeof(STR_MANUFACTURER)}, + {0x0302, 0x0409, (const uint8_t *)&string2, sizeof(STR_PRODUCT)}, + {0x0303, 0x0409, (const uint8_t *)&string3, sizeof(STR_SERIAL_NUMBER)} +}; +#define NUM_DESC_LIST (sizeof(descriptor_list)/sizeof(struct descriptor_list_struct)) + + +/************************************************************************** + * + * Variables - these are the only non-stack RAM usage + * + **************************************************************************/ + +// zero when we are not configured, non-zero when enumerated +static volatile uint8_t usb_configuration=0; + +// the time remaining before we transmit any partially full +// packet, or send a zero length packet. +static volatile uint8_t transmit_flush_timer=0; +static uint8_t transmit_previous_timeout=0; + +// serial port settings (baud rate, control signals, etc) set +// by the PC. These are ignored, but kept in RAM. +static uint8_t cdc_line_coding[7]={0x00, 0xE1, 0x00, 0x00, 0x00, 0x00, 0x08}; +static uint8_t cdc_line_rtsdtr=0; + + +/************************************************************************** + * + * Public Functions - these are the API intended for the user + * + **************************************************************************/ + +// initialize USB serial +void usb_init(void) +{ + HW_CONFIG(); + USB_FREEZE(); // enable USB + PLL_CONFIG(); // config PLL, 16 MHz xtal + while (!(PLLCSR & (1<<PLOCK))) ; // wait for PLL lock + USB_CONFIG(); // start USB clock + UDCON = 0; // enable attach resistor + usb_configuration = 0; + cdc_line_rtsdtr = 0; + UDIEN = (1<<EORSTE)|(1<<SOFE); + sei(); +} + +// return 0 if the USB is not configured, or the configuration +// number selected by the HOST +uint8_t usb_configured(void) +{ + return usb_configuration; +} + +// get the next character, or -1 if nothing received +int16_t usb_serial_getchar(void) +{ + uint8_t c, intr_state; + + // interrupts are disabled so these functions can be + // used from the main program or interrupt context, + // even both in the same program! + intr_state = SREG; + cli(); + if (!usb_configuration) { + SREG = intr_state; + return -1; + } + UENUM = CDC_RX_ENDPOINT; + retry: + c = UEINTX; + if (!(c & (1<<RWAL))) { + // no data in buffer + if (c & (1<<RXOUTI)) { + UEINTX = 0x6B; + goto retry; + } + SREG = intr_state; + return -1; + } + // take one byte out of the buffer + c = UEDATX; + // if buffer completely used, release it + if (!(UEINTX & (1<<RWAL))) UEINTX = 0x6B; + SREG = intr_state; + return c; +} + +// number of bytes available in the receive buffer +uint8_t usb_serial_available(void) +{ + uint8_t n=0, i, intr_state; + + intr_state = SREG; + cli(); + if (usb_configuration) { + UENUM = CDC_RX_ENDPOINT; + n = UEBCLX; + if (!n) { + i = UEINTX; + if (i & (1<<RXOUTI) && !(i & (1<<RWAL))) UEINTX = 0x6B; + } + } + SREG = intr_state; + return n; +} + +// discard any buffered input +void usb_serial_flush_input(void) +{ + uint8_t intr_state; + + if (usb_configuration) { + intr_state = SREG; + cli(); + UENUM = CDC_RX_ENDPOINT; + while ((UEINTX & (1<<RWAL))) { + UEINTX = 0x6B; + } + SREG = intr_state; + } +} + +// transmit a character. 0 returned on success, -1 on error +int8_t usb_serial_putchar(uint8_t c) +{ + uint8_t timeout, intr_state; + + // if we're not online (enumerated and configured), error + if (!usb_configuration) return -1; + // interrupts are disabled so these functions can be + // used from the main program or interrupt context, + // even both in the same program! + intr_state = SREG; + cli(); + UENUM = CDC_TX_ENDPOINT; + // if we gave up due to timeout before, don't wait again + if (transmit_previous_timeout) { + if (!(UEINTX & (1<<RWAL))) { + SREG = intr_state; + return -1; + } + transmit_previous_timeout = 0; + } + // wait for the FIFO to be ready to accept data + timeout = UDFNUML + TRANSMIT_TIMEOUT; + while (1) { + // are we ready to transmit? + if (UEINTX & (1<<RWAL)) break; + SREG = intr_state; + // have we waited too long? This happens if the user + // is not running an application that is listening + if (UDFNUML == timeout) { + transmit_previous_timeout = 1; + return -1; + } + // has the USB gone offline? + if (!usb_configuration) return -1; + // get ready to try checking again + intr_state = SREG; + cli(); + UENUM = CDC_TX_ENDPOINT; + } + // actually write the byte into the FIFO + UEDATX = c; + // if this completed a packet, transmit it now! + if (!(UEINTX & (1<<RWAL))) UEINTX = 0x3A; + transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT; + SREG = intr_state; + return 0; +} + + +// transmit a character, but do not wait if the buffer is full, +// 0 returned on success, -1 on buffer full or error +int8_t usb_serial_putchar_nowait(uint8_t c) +{ + uint8_t intr_state; + + if (!usb_configuration) return -1; + intr_state = SREG; + cli(); + UENUM = CDC_TX_ENDPOINT; + if (!(UEINTX & (1<<RWAL))) { + // buffer is full + SREG = intr_state; + return -1; + } + // actually write the byte into the FIFO + UEDATX = c; + // if this completed a packet, transmit it now! + if (!(UEINTX & (1<<RWAL))) UEINTX = 0x3A; + transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT; + SREG = intr_state; + return 0; +} + +// transmit a buffer. +// 0 returned on success, -1 on error +// This function is optimized for speed! Each call takes approx 6.1 us overhead +// plus 0.25 us per byte. 12 Mbit/sec USB has 8.67 us per-packet overhead and +// takes 0.67 us per byte. If called with 64 byte packet-size blocks, this function +// can transmit at full USB speed using 43% CPU time. The maximum theoretical speed +// is 19 packets per USB frame, or 1216 kbytes/sec. However, bulk endpoints have the +// lowest priority, so any other USB devices will likely reduce the speed. Speed +// can also be limited by how quickly the PC-based software reads data, as the host +// controller in the PC will not allocate bandwitdh without a pending read request. +// (thanks to Victor Suarez for testing and feedback and initial code) + +int8_t usb_serial_write(const uint8_t *buffer, uint16_t size) +{ + uint8_t timeout, intr_state, write_size; + + // if we're not online (enumerated and configured), error + if (!usb_configuration) return -1; + // interrupts are disabled so these functions can be + // used from the main program or interrupt context, + // even both in the same program! + intr_state = SREG; + cli(); + UENUM = CDC_TX_ENDPOINT; + // if we gave up due to timeout before, don't wait again + if (transmit_previous_timeout) { + if (!(UEINTX & (1<<RWAL))) { + SREG = intr_state; + return -1; + } + transmit_previous_timeout = 0; + } + // each iteration of this loop transmits a packet + while (size) { + // wait for the FIFO to be ready to accept data + timeout = UDFNUML + TRANSMIT_TIMEOUT; + while (1) { + // are we ready to transmit? + if (UEINTX & (1<<RWAL)) break; + SREG = intr_state; + // have we waited too long? This happens if the user + // is not running an application that is listening + if (UDFNUML == timeout) { + transmit_previous_timeout = 1; + return -1; + } + // has the USB gone offline? + if (!usb_configuration) return -1; + // get ready to try checking again + intr_state = SREG; + cli(); + UENUM = CDC_TX_ENDPOINT; + } + + // compute how many bytes will fit into the next packet + write_size = CDC_TX_SIZE - UEBCLX; + if (write_size > size) write_size = size; + size -= write_size; + + // write the packet + switch (write_size) { + #if (CDC_TX_SIZE == 64) + case 64: UEDATX = *buffer++; + case 63: UEDATX = *buffer++; + case 62: UEDATX = *buffer++; + case 61: UEDATX = *buffer++; + case 60: UEDATX = *buffer++; + case 59: UEDATX = *buffer++; + case 58: UEDATX = *buffer++; + case 57: UEDATX = *buffer++; + case 56: UEDATX = *buffer++; + case 55: UEDATX = *buffer++; + case 54: UEDATX = *buffer++; + case 53: UEDATX = *buffer++; + case 52: UEDATX = *buffer++; + case 51: UEDATX = *buffer++; + case 50: UEDATX = *buffer++; + case 49: UEDATX = *buffer++; + case 48: UEDATX = *buffer++; + case 47: UEDATX = *buffer++; + case 46: UEDATX = *buffer++; + case 45: UEDATX = *buffer++; + case 44: UEDATX = *buffer++; + case 43: UEDATX = *buffer++; + case 42: UEDATX = *buffer++; + case 41: UEDATX = *buffer++; + case 40: UEDATX = *buffer++; + case 39: UEDATX = *buffer++; + case 38: UEDATX = *buffer++; + case 37: UEDATX = *buffer++; + case 36: UEDATX = *buffer++; + case 35: UEDATX = *buffer++; + case 34: UEDATX = *buffer++; + case 33: UEDATX = *buffer++; + #endif + #if (CDC_TX_SIZE >= 32) + case 32: UEDATX = *buffer++; + case 31: UEDATX = *buffer++; + case 30: UEDATX = *buffer++; + case 29: UEDATX = *buffer++; + case 28: UEDATX = *buffer++; + case 27: UEDATX = *buffer++; + case 26: UEDATX = *buffer++; + case 25: UEDATX = *buffer++; + case 24: UEDATX = *buffer++; + case 23: UEDATX = *buffer++; + case 22: UEDATX = *buffer++; + case 21: UEDATX = *buffer++; + case 20: UEDATX = *buffer++; + case 19: UEDATX = *buffer++; + case 18: UEDATX = *buffer++; + case 17: UEDATX = *buffer++; + #endif + #if (CDC_TX_SIZE >= 16) + case 16: UEDATX = *buffer++; + case 15: UEDATX = *buffer++; + case 14: UEDATX = *buffer++; + case 13: UEDATX = *buffer++; + case 12: UEDATX = *buffer++; + case 11: UEDATX = *buffer++; + case 10: UEDATX = *buffer++; + case 9: UEDATX = *buffer++; + #endif + case 8: UEDATX = *buffer++; + case 7: UEDATX = *buffer++; + case 6: UEDATX = *buffer++; + case 5: UEDATX = *buffer++; + case 4: UEDATX = *buffer++; + case 3: UEDATX = *buffer++; + case 2: UEDATX = *buffer++; + default: + case 1: UEDATX = *buffer++; + case 0: break; + } + // if this completed a packet, transmit it now! + if (!(UEINTX & (1<<RWAL))) UEINTX = 0x3A; + transmit_flush_timer = TRANSMIT_FLUSH_TIMEOUT; + SREG = intr_state; + } + return 0; +} + + +// immediately transmit any buffered output. +// This doesn't actually transmit the data - that is impossible! +// USB devices only transmit when the host allows, so the best +// we can do is release the FIFO buffer for when the host wants it +void usb_serial_flush_output(void) +{ + uint8_t intr_state; + + intr_state = SREG; + cli(); + if (transmit_flush_timer) { + UENUM = CDC_TX_ENDPOINT; + UEINTX = 0x3A; + transmit_flush_timer = 0; + } + SREG = intr_state; +} + +// functions to read the various async serial settings. These +// aren't actually used by USB at all (communication is always +// at full USB speed), but they are set by the host so we can +// set them properly if we're converting the USB to a real serial +// communication +uint32_t usb_serial_get_baud(void) +{ + char *c=(char *) cdc_line_coding; + uint32_t *ret=(uint32_t *) c; + return *ret; +} +uint8_t usb_serial_get_stopbits(void) +{ + return cdc_line_coding[4]; +} +uint8_t usb_serial_get_paritytype(void) +{ + return cdc_line_coding[5]; +} +uint8_t usb_serial_get_numbits(void) +{ + return cdc_line_coding[6]; +} +uint8_t usb_serial_get_control(void) +{ + return cdc_line_rtsdtr; +} +// write the control signals, DCD, DSR, RI, etc +// There is no CTS signal. If software on the host has transmitted +// data to you but you haven't been calling the getchar function, +// it remains buffered (either here or on the host) and can not be +// lost because you weren't listening at the right time, like it +// would in real serial communication. +int8_t usb_serial_set_control(uint8_t signals) +{ + uint8_t intr_state; + + intr_state = SREG; + cli(); + if (!usb_configuration) { + // we're not enumerated/configured + SREG = intr_state; + return -1; + } + + UENUM = CDC_ACM_ENDPOINT; + if (!(UEINTX & (1<<RWAL))) { + // unable to write + // TODO; should this try to abort the previously + // buffered message?? + SREG = intr_state; + return -1; + } + UEDATX = 0xA1; + UEDATX = 0x20; + UEDATX = 0; + UEDATX = 0; + UEDATX = 0; // 0 seems to work nicely. what if this is 1?? + UEDATX = 0; + UEDATX = 1; + UEDATX = 0; + UEDATX = signals; + UEINTX = 0x3A; + SREG = intr_state; + return 0; +} + + + +/************************************************************************** + * + * Private Functions - not intended for general user consumption.... + * + **************************************************************************/ + + +// USB Device Interrupt - handle all device-level events +// the transmit buffer flushing is triggered by the start of frame +// +ISR(USB_GEN_vect) +{ + uint8_t intbits, t; + + intbits = UDINT; + UDINT = 0; + if (intbits & (1<<EORSTI)) { + UENUM = 0; + UECONX = 1; + UECFG0X = EP_TYPE_CONTROL; + UECFG1X = EP_SIZE(ENDPOINT0_SIZE) | EP_SINGLE_BUFFER; + UEIENX = (1<<RXSTPE); + usb_configuration = 0; + cdc_line_rtsdtr = 0; + } + if (intbits & (1<<SOFI)) { + if (usb_configuration) { + t = transmit_flush_timer; + if (t) { + transmit_flush_timer = --t; + if (!t) { + UENUM = CDC_TX_ENDPOINT; + UEINTX = 0x3A; + } + } + } + } +} + + +// Misc functions to wait for ready and send/receive packets +static inline void usb_wait_in_ready(void) +{ + while (!(UEINTX & (1<<TXINI))) ; +} +static inline void usb_send_in(void) +{ + UEINTX = ~(1<<TXINI); +} +static inline void usb_wait_receive_out(void) +{ + while (!(UEINTX & (1<<RXOUTI))) ; +} +static inline void usb_ack_out(void) +{ + UEINTX = ~(1<<RXOUTI); +} + + + +// USB Endpoint Interrupt - endpoint 0 is handled here. The +// other endpoints are manipulated by the user-callable +// functions, and the start-of-frame interrupt. +// +ISR(USB_COM_vect) +{ + uint8_t intbits; + const uint8_t *list; + const uint8_t *cfg; + uint8_t i, n, len, en; + uint8_t *p; + uint8_t bmRequestType; + uint8_t bRequest; + uint16_t wValue; + uint16_t wIndex; + uint16_t wLength; + uint16_t desc_val; + const uint8_t *desc_addr; + uint8_t desc_length; + + UENUM = 0; + intbits = UEINTX; + if (intbits & (1<<RXSTPI)) { + bmRequestType = UEDATX; + bRequest = UEDATX; + wValue = UEDATX; + wValue |= (UEDATX << 8); + wIndex = UEDATX; + wIndex |= (UEDATX << 8); + wLength = UEDATX; + wLength |= (UEDATX << 8); + UEINTX = ~((1<<RXSTPI) | (1<<RXOUTI) | (1<<TXINI)); + if (bRequest == GET_DESCRIPTOR) { + list = (const uint8_t *)descriptor_list; + for (i=0; ; i++) { + if (i >= NUM_DESC_LIST) { + UECONX = (1<<STALLRQ)|(1<<EPEN); //stall + return; + } + desc_val = pgm_read_word(list); + if (desc_val != wValue) { + list += sizeof(struct descriptor_list_struct); + continue; + } + list += 2; + desc_val = pgm_read_word(list); + if (desc_val != wIndex) { + list += sizeof(struct descriptor_list_struct)-2; + continue; + } + list += 2; + desc_addr = (const uint8_t *)pgm_read_word(list); + list += 2; + desc_length = pgm_read_byte(list); + break; + } + len = (wLength < 256) ? wLength : 255; + if (len > desc_length) len = desc_length; + do { + // wait for host ready for IN packet + do { + i = UEINTX; + } while (!(i & ((1<<TXINI)|(1<<RXOUTI)))); + if (i & (1<<RXOUTI)) return; // abort + // send IN packet + n = len < ENDPOINT0_SIZE ? len : ENDPOINT0_SIZE; + for (i = n; i; i--) { + UEDATX = pgm_read_byte(desc_addr++); + } + len -= n; + usb_send_in(); + } while (len || n == ENDPOINT0_SIZE); + return; + } + if (bRequest == SET_ADDRESS) { + usb_send_in(); + usb_wait_in_ready(); + UDADDR = wValue | (1<<ADDEN); + return; + } + if (bRequest == SET_CONFIGURATION && bmRequestType == 0) { + usb_configuration = wValue; + cdc_line_rtsdtr = 0; + transmit_flush_timer = 0; + usb_send_in(); + cfg = endpoint_config_table; + for (i=1; i<5; i++) { + UENUM = i; + en = pgm_read_byte(cfg++); + UECONX = en; + if (en) { + UECFG0X = pgm_read_byte(cfg++); + UECFG1X = pgm_read_byte(cfg++); + } + } + UERST = 0x1E; + UERST = 0; + return; + } + if (bRequest == GET_CONFIGURATION && bmRequestType == 0x80) { + usb_wait_in_ready(); + UEDATX = usb_configuration; + usb_send_in(); + return; + } + if (bRequest == CDC_GET_LINE_CODING && bmRequestType == 0xA1) { + usb_wait_in_ready(); + p = cdc_line_coding; + for (i=0; i<7; i++) { + UEDATX = *p++; + } + usb_send_in(); + return; + } + if (bRequest == CDC_SET_LINE_CODING && bmRequestType == 0x21) { + usb_wait_receive_out(); + p = cdc_line_coding; + for (i=0; i<7; i++) { + *p++ = UEDATX; + } + usb_ack_out(); + usb_send_in(); + return; + } + if (bRequest == CDC_SET_CONTROL_LINE_STATE && bmRequestType == 0x21) { + cdc_line_rtsdtr = wValue; + usb_wait_in_ready(); + usb_send_in(); + return; + } + if (bRequest == GET_STATUS) { + usb_wait_in_ready(); + i = 0; + #ifdef SUPPORT_ENDPOINT_HALT + if (bmRequestType == 0x82) { + UENUM = wIndex; + if (UECONX & (1<<STALLRQ)) i = 1; + UENUM = 0; + } + #endif + UEDATX = i; + UEDATX = 0; + usb_send_in(); + return; + } + #ifdef SUPPORT_ENDPOINT_HALT + if ((bRequest == CLEAR_FEATURE || bRequest == SET_FEATURE) + && bmRequestType == 0x02 && wValue == 0) { + i = wIndex & 0x7F; + if (i >= 1 && i <= MAX_ENDPOINT) { + usb_send_in(); + UENUM = i; + if (bRequest == SET_FEATURE) { + UECONX = (1<<STALLRQ)|(1<<EPEN); + } else { + UECONX = (1<<STALLRQC)|(1<<RSTDT)|(1<<EPEN); + UERST = (1 << i); + UERST = 0; + } + return; + } + } + #endif + } + UECONX = (1<<STALLRQ) | (1<<EPEN); // stall +} + + |