From cfec7864e97876305cf7cfffacf184257a1cf274 Mon Sep 17 00:00:00 2001 From: "David A. Mellis" Date: Thu, 1 Nov 2012 10:45:50 -0400 Subject: Adding LilyPad Arduino USB. --- bootloaders/caterina-LilyPadUSB/Caterina.c | 780 +++++++++++++++++++++++++++++ 1 file changed, 780 insertions(+) create mode 100755 bootloaders/caterina-LilyPadUSB/Caterina.c (limited to 'bootloaders/caterina-LilyPadUSB/Caterina.c') diff --git a/bootloaders/caterina-LilyPadUSB/Caterina.c b/bootloaders/caterina-LilyPadUSB/Caterina.c new file mode 100755 index 0000000..9a59081 --- /dev/null +++ b/bootloaders/caterina-LilyPadUSB/Caterina.c @@ -0,0 +1,780 @@ +/* + LUFA Library + Copyright (C) Dean Camera, 2011. + + dean [at] fourwalledcubicle [dot] com + www.lufa-lib.org +*/ + +/* + Copyright 2011 Dean Camera (dean [at] fourwalledcubicle [dot] com) + + Permission to use, copy, modify, distribute, and sell this + software and its documentation for any purpose is hereby granted + without fee, provided that the above copyright notice appear in + all copies and that both that the copyright notice and this + permission notice and warranty disclaimer appear in supporting + documentation, and that the name of the author not be used in + advertising or publicity pertaining to distribution of the + software without specific, written prior permission. + + The author disclaim all warranties with regard to this + software, including all implied warranties of merchantability + and fitness. In no event shall the author be liable for any + special, indirect or consequential damages or any damages + whatsoever resulting from loss of use, data or profits, whether + in an action of contract, negligence or other tortious action, + arising out of or in connection with the use or performance of + this software. +*/ + +/** \file + * + * Main source file for the CDC class bootloader. This file contains the complete bootloader logic. + */ + +#define INCLUDE_FROM_CATERINA_C +#include "Caterina.h" + +/** Contains the current baud rate and other settings of the first virtual serial port. This must be retained as some + * operating systems will not open the port unless the settings can be set successfully. + */ +static CDC_LineEncoding_t LineEncoding = { .BaudRateBPS = 0, + .CharFormat = CDC_LINEENCODING_OneStopBit, + .ParityType = CDC_PARITY_None, + .DataBits = 8 }; + +/** Current address counter. This stores the current address of the FLASH or EEPROM as set by the host, + * and is used when reading or writing to the AVRs memory (either FLASH or EEPROM depending on the issued + * command.) + */ +static uint32_t CurrAddress; + +/** Flag to indicate if the bootloader should be running, or should exit and allow the application code to run + * via a watchdog reset. When cleared the bootloader will exit, starting the watchdog and entering an infinite + * loop until the AVR restarts and the application runs. + */ +static bool RunBootloader = true; + +/* Pulse generation counters to keep track of the time remaining for each pulse type */ +#define TX_RX_LED_PULSE_PERIOD 100 +uint16_t TxLEDPulse = 0; // time remaining for Tx LED pulse +uint16_t RxLEDPulse = 0; // time remaining for Rx LED pulse + +/* Bootloader timeout timer */ +// MAH 8/15/12- change so timeouts work properly when the chip is running at 8MHz instead of 16. +#define TIMEOUT_PERIOD 4000 +#define EXT_RESET_TIMEOUT_PERIOD 375 + + +/********************************************************************************************************* +LilyPadUSB bootloader code +The LilyPadUSB bootloader has been changed to remove the 8-second delay after external reset which is in +the Leonardo. To enter the bootloader, the user should execute TWO external resets within 750 ms; that is, +press the reset button twice, quickly.\ + +Some other changes were made to allow this code to compile tightly enough to fit in the alloted 4k of +bootloader space. +*/ +// MAH 8/15/12- added this flag to replace the bulky program memory reads to check for the presence of a sketch +// at the top of the memory space. +static bool sketchPresent = false; + +// MAH 8/15/12- make this volatile, since we modify it in one place and read it in another, we want to make +// sure we're always working on the copy in memory and not an erroneous value stored in a cache somewhere. +// This variable stores the length of time we've been in the bootloader when waiting for the 8 second delay. +volatile uint16_t Timeout = 0; +// MAH 8/15/12- added this for delay during startup. Did not use existing Timeout value b/c it only increments +// when there's a sketch at the top of the memory. +volatile uint16_t resetTimeout = 0; + +// MAH 8/15/12- let's make this an 8-bit value instead of 16- that saves on memory because 16-bit addition and +// comparison compiles to bulkier code. Note that this does *not* require a change to the Arduino core- we're +// just sort of ignoring the extra byte that the Arduino core puts at the next location. +uint8_t bootKey = 0x77; +volatile uint8_t *const bootKeyPtr = (volatile uint8_t *)0x0800; + +// StartSketch() is called to clean up our mess before passing execution to the sketch. +void StartSketch(void) +{ + cli(); + + /* Undo TIMER1 setup and clear the count before running the sketch */ + TIMSK1 = 0; + TCCR1B = 0; + + /* Relocate the interrupt vector table to the application section */ + MCUCR = (1 << IVCE); + MCUCR = 0; + + L_LED_OFF(); + TX_LED_OFF(); + RX_LED_OFF(); + + /* jump to beginning of application space */ + __asm__ volatile("jmp 0x0000"); + +} + +uint16_t LLEDPulse; + +/** Main program entry point. This routine configures the hardware required by the bootloader, then continuously + * runs the bootloader processing routine until it times out or is instructed to exit. + */ +int main(void) +{ + /* Save the value of the boot key memory before it is overwritten */ + uint8_t bootKeyPtrVal = *bootKeyPtr; + *bootKeyPtr = 0; + + /* Check the reason for the reset so we can act accordingly */ + uint8_t mcusr_state = MCUSR; // store the initial state of the Status register + MCUSR = 0; // clear all reset flags + + /* Watchdog may be configured with a 15 ms period so must disable it before going any further */ + // MAH 8/15/12- I removed this because wdt_disable() is the first thing SetupHardware() does- why + // do it twice right in a row? + //wdt_disable(); + + /* Setup hardware required for the bootloader */ + // MAH 8/15/12- Moved this up to before the bootloader go/no-go decision tree so I could use the + // timer in that decision tree. Removed the USBInit() call from it; if I'm not going to stay in + // the bootloader, there's no point spending the time initializing the USB. + // SetupHardware(); + wdt_disable(); + + // Disable clock division + clock_prescale_set(clock_div_1); + + // Relocate the interrupt vector table to the bootloader section + MCUCR = (1 << IVCE); + MCUCR = (1 << IVSEL); + + LED_SETUP(); + CPU_PRESCALE(0); + L_LED_OFF(); + TX_LED_OFF(); + RX_LED_OFF(); + + // Initialize TIMER1 to handle bootloader timeout and LED tasks. + // With 16 MHz clock and 1/64 prescaler, timer 1 is clocked at 250 kHz + // Our chosen compare match generates an interrupt every 1 ms. + // This interrupt is disabled selectively when doing memory reading, erasing, + // or writing since SPM has tight timing requirements. + + OCR1AH = 0; + OCR1AL = 250; + TIMSK1 = (1 << OCIE1A); // enable timer 1 output compare A match interrupt + TCCR1B = ((1 << CS11) | (1 << CS10)); // 1/64 prescaler on timer 1 input + + + // MAH 8/15/12- this replaces bulky pgm_read_word(0) calls later on, to save memory. + if (pgm_read_word(0) != 0xFFFF) sketchPresent = true; + +// MAH 26 Oct 2012- The "bootload or not?" section has been modified since the code released +// with Arduino 1.0.1. The simplest modification is the replacement of equivalence checks on +// the reset bits with masked checks, so if more than one reset occurs before the register is +// checked, the check doesn't fail and fall through to the bootloader unnecessarily. + +// The second, more in depth modification addresses behavior after an external reset (i.e., +// user pushes the reset button). The Leonardo treats all external resets as requests to +// re-enter the bootloader and wait for code to be loaded. It remains in bootloader mode for +// 8 seconds before continuing on to the sketch (if one is present). By defining RESET_DELAY +// equal to 1, this behavior will persist. + +// However, if RESET_DELAY is defined to 0, the reset timeout before loading the sketch drops +// to 750ms. If, during that 750ms, another external reset occurs, THEN an 8-second delay +// in the bootloader will occur. + + // This is the "no-8-second-delay" code. If this is the first time through the loop, we + // don't expect to see the bootKey in memory. + if ( (mcusr_state & (1< EXT_RESET_TIMEOUT_PERIOD) // resetTimeout is getting incremeted + RunBootloader = false; // in the timer1 ISR. + } + // If we make it past that while loop, it's sketch loading time! + *bootKeyPtr = 0; // clear out the bootKey; from now on, we want to treat a reset like + // a normal reset. + cli(); // Disable interrupts, in case no sketch is present. + RunBootloader = true; // We want to hang out in the bootloader if no sketch is present. + if (sketchPresent) StartSketch(); // If a sketch is present, go! Otherwise, wait around + // in the bootloader until one is uploaded. + } + // On a power-on reset, we ALWAYS want to go to the sketch. If there is one. + // This is a place where the old code had an equivalence and now there is a mask. + else if ( (mcusr_state & (1< TIMEOUT_PERIOD) + RunBootloader = false; + + // MAH 8/15/12- This used to be a function call- inlining it saves a few bytes. + LLEDPulse++; + uint8_t p = LLEDPulse >> 8; + if (p > 127) + p = 254-p; + p += p; + if (((uint8_t)LLEDPulse) > p) + L_LED_OFF(); + else + L_LED_ON(); + } + + /* Disconnect from the host - USB interface will be reset later along with the AVR */ + USB_Detach(); + + /* Jump to beginning of application space to run the sketch - do not reset */ + StartSketch(); +} + +// Timer1 is set up to provide periodic interrupts. This is used to flicker the LEDs during +// programming as well as to generate the clock counts which determine how long the board should +// remain in bootloading mode. + +ISR(TIMER1_COMPA_vect, ISR_BLOCK) +{ + /* Reset counter */ + TCNT1H = 0; + TCNT1L = 0; + + /* Check whether the TX or RX LED one-shot period has elapsed. if so, turn off the LED */ + if (TxLEDPulse && !(--TxLEDPulse)) + TX_LED_OFF(); + if (RxLEDPulse && !(--RxLEDPulse)) + RX_LED_OFF(); + resetTimeout++; // Needed for the "short reset delay" mode- governs the time the board waits + // for a second reset before loading the sketch. + if (pgm_read_word(0) != 0xFFFF) + Timeout++; +} + +// MAH 29 Oct 2012 Nothing below this point has to change for the LilyPadUSB support + +/** Event handler for the USB_ConfigurationChanged event. This configures the device's endpoints ready + * to relay data to and from the attached USB host. + */ +void EVENT_USB_Device_ConfigurationChanged(void) +{ + /* Setup CDC Notification, Rx and Tx Endpoints */ + Endpoint_ConfigureEndpoint(CDC_NOTIFICATION_EPNUM, EP_TYPE_INTERRUPT, + ENDPOINT_DIR_IN, CDC_NOTIFICATION_EPSIZE, + ENDPOINT_BANK_SINGLE); + + Endpoint_ConfigureEndpoint(CDC_TX_EPNUM, EP_TYPE_BULK, + ENDPOINT_DIR_IN, CDC_TXRX_EPSIZE, + ENDPOINT_BANK_SINGLE); + + Endpoint_ConfigureEndpoint(CDC_RX_EPNUM, EP_TYPE_BULK, + ENDPOINT_DIR_OUT, CDC_TXRX_EPSIZE, + ENDPOINT_BANK_SINGLE); +} + +/** Event handler for the USB_ControlRequest event. This is used to catch and process control requests sent to + * the device from the USB host before passing along unhandled control requests to the library for processing + * internally. + */ +void EVENT_USB_Device_ControlRequest(void) +{ + /* Ignore any requests that aren't directed to the CDC interface */ + if ((USB_ControlRequest.bmRequestType & (CONTROL_REQTYPE_TYPE | CONTROL_REQTYPE_RECIPIENT)) != + (REQTYPE_CLASS | REQREC_INTERFACE)) + { + return; + } + + /* Process CDC specific control requests */ + switch (USB_ControlRequest.bRequest) + { + case CDC_REQ_GetLineEncoding: + if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE)) + { + Endpoint_ClearSETUP(); + + /* Write the line coding data to the control endpoint */ + Endpoint_Write_Control_Stream_LE(&LineEncoding, sizeof(CDC_LineEncoding_t)); + Endpoint_ClearOUT(); + } + + break; + case CDC_REQ_SetLineEncoding: + if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE)) + { + Endpoint_ClearSETUP(); + + /* Read the line coding data in from the host into the global struct */ + Endpoint_Read_Control_Stream_LE(&LineEncoding, sizeof(CDC_LineEncoding_t)); + Endpoint_ClearIN(); + } + + break; + } +} + +#if !defined(NO_BLOCK_SUPPORT) +/** Reads or writes a block of EEPROM or FLASH memory to or from the appropriate CDC data endpoint, depending + * on the AVR910 protocol command issued. + * + * \param[in] Command Single character AVR910 protocol command indicating what memory operation to perform + */ +static void ReadWriteMemoryBlock(const uint8_t Command) +{ + uint16_t BlockSize; + char MemoryType; + + bool HighByte = false; + uint8_t LowByte = 0; + + BlockSize = (FetchNextCommandByte() << 8); + BlockSize |= FetchNextCommandByte(); + + MemoryType = FetchNextCommandByte(); + + if ((MemoryType != 'E') && (MemoryType != 'F')) + { + /* Send error byte back to the host */ + WriteNextResponseByte('?'); + + return; + } + + /* Disable timer 1 interrupt - can't afford to process nonessential interrupts + * while doing SPM tasks */ + TIMSK1 = 0; + + /* Check if command is to read memory */ + if (Command == 'g') + { + /* Re-enable RWW section */ + boot_rww_enable(); + + while (BlockSize--) + { + if (MemoryType == 'F') + { + /* Read the next FLASH byte from the current FLASH page */ + #if (FLASHEND > 0xFFFF) + WriteNextResponseByte(pgm_read_byte_far(CurrAddress | HighByte)); + #else + WriteNextResponseByte(pgm_read_byte(CurrAddress | HighByte)); + #endif + + /* If both bytes in current word have been read, increment the address counter */ + if (HighByte) + CurrAddress += 2; + + HighByte = !HighByte; + } + else + { + /* Read the next EEPROM byte into the endpoint */ + WriteNextResponseByte(eeprom_read_byte((uint8_t*)(intptr_t)(CurrAddress >> 1))); + + /* Increment the address counter after use */ + CurrAddress += 2; + } + } + } + else + { + uint32_t PageStartAddress = CurrAddress; + + if (MemoryType == 'F') + { + boot_page_erase(PageStartAddress); + boot_spm_busy_wait(); + } + + while (BlockSize--) + { + if (MemoryType == 'F') + { + /* If both bytes in current word have been written, increment the address counter */ + if (HighByte) + { + /* Write the next FLASH word to the current FLASH page */ + boot_page_fill(CurrAddress, ((FetchNextCommandByte() << 8) | LowByte)); + + /* Increment the address counter after use */ + CurrAddress += 2; + } + else + { + LowByte = FetchNextCommandByte(); + } + + HighByte = !HighByte; + } + else + { + /* Write the next EEPROM byte from the endpoint */ + eeprom_write_byte((uint8_t*)((intptr_t)(CurrAddress >> 1)), FetchNextCommandByte()); + + /* Increment the address counter after use */ + CurrAddress += 2; + } + } + + /* If in FLASH programming mode, commit the page after writing */ + if (MemoryType == 'F') + { + /* Commit the flash page to memory */ + boot_page_write(PageStartAddress); + + /* Wait until write operation has completed */ + boot_spm_busy_wait(); + } + + /* Send response byte back to the host */ + WriteNextResponseByte('\r'); + } + + /* Re-enable timer 1 interrupt disabled earlier in this routine */ + TIMSK1 = (1 << OCIE1A); +} +#endif + +/** Retrieves the next byte from the host in the CDC data OUT endpoint, and clears the endpoint bank if needed + * to allow reception of the next data packet from the host. + * + * \return Next received byte from the host in the CDC data OUT endpoint + */ +static uint8_t FetchNextCommandByte(void) +{ + /* Select the OUT endpoint so that the next data byte can be read */ + Endpoint_SelectEndpoint(CDC_RX_EPNUM); + + /* If OUT endpoint empty, clear it and wait for the next packet from the host */ + while (!(Endpoint_IsReadWriteAllowed())) + { + Endpoint_ClearOUT(); + + while (!(Endpoint_IsOUTReceived())) + { + if (USB_DeviceState == DEVICE_STATE_Unattached) + return 0; + } + } + + /* Fetch the next byte from the OUT endpoint */ + return Endpoint_Read_8(); +} + +/** Writes the next response byte to the CDC data IN endpoint, and sends the endpoint back if needed to free up the + * bank when full ready for the next byte in the packet to the host. + * + * \param[in] Response Next response byte to send to the host + */ +static void WriteNextResponseByte(const uint8_t Response) +{ + /* Select the IN endpoint so that the next data byte can be written */ + Endpoint_SelectEndpoint(CDC_TX_EPNUM); + + /* If IN endpoint full, clear it and wait until ready for the next packet to the host */ + if (!(Endpoint_IsReadWriteAllowed())) + { + Endpoint_ClearIN(); + + while (!(Endpoint_IsINReady())) + { + if (USB_DeviceState == DEVICE_STATE_Unattached) + return; + } + } + + /* Write the next byte to the IN endpoint */ + Endpoint_Write_8(Response); + + TX_LED_ON(); + TxLEDPulse = TX_RX_LED_PULSE_PERIOD; +} + +#define STK_OK 0x10 +#define STK_INSYNC 0x14 // ' ' +#define CRC_EOP 0x20 // 'SPACE' +#define STK_GET_SYNC 0x30 // '0' + +#define STK_GET_PARAMETER 0x41 // 'A' +#define STK_SET_DEVICE 0x42 // 'B' +#define STK_SET_DEVICE_EXT 0x45 // 'E' +#define STK_LOAD_ADDRESS 0x55 // 'U' +#define STK_UNIVERSAL 0x56 // 'V' +#define STK_PROG_PAGE 0x64 // 'd' +#define STK_READ_PAGE 0x74 // 't' +#define STK_READ_SIGN 0x75 // 'u' + +/** Task to read in AVR910 commands from the CDC data OUT endpoint, process them, perform the required actions + * and send the appropriate response back to the host. + */ +void CDC_Task(void) +{ + /* Select the OUT endpoint */ + Endpoint_SelectEndpoint(CDC_RX_EPNUM); + + /* Check if endpoint has a command in it sent from the host */ + if (!(Endpoint_IsOUTReceived())) + return; + + RX_LED_ON(); + RxLEDPulse = TX_RX_LED_PULSE_PERIOD; + + /* Read in the bootloader command (first byte sent from host) */ + uint8_t Command = FetchNextCommandByte(); + + if (Command == 'E') + { + /* We nearly run out the bootloader timeout clock, + * leaving just a few hundred milliseconds so the + * bootloder has time to respond and service any + * subsequent requests */ + Timeout = TIMEOUT_PERIOD - 500; + + /* Re-enable RWW section - must be done here in case + * user has disabled verification on upload. */ + boot_rww_enable_safe(); + + // Send confirmation byte back to the host + WriteNextResponseByte('\r'); + } + else if (Command == 'T') + { + FetchNextCommandByte(); + + // Send confirmation byte back to the host + WriteNextResponseByte('\r'); + } + else if ((Command == 'L') || (Command == 'P')) + { + // Send confirmation byte back to the host + WriteNextResponseByte('\r'); + } + else if (Command == 't') + { + // Return ATMEGA128 part code - this is only to allow AVRProg to use the bootloader + WriteNextResponseByte(0x44); + WriteNextResponseByte(0x00); + } + else if (Command == 'a') + { + // Indicate auto-address increment is supported + WriteNextResponseByte('Y'); + } + else if (Command == 'A') + { + // Set the current address to that given by the host + CurrAddress = (FetchNextCommandByte() << 9); + CurrAddress |= (FetchNextCommandByte() << 1); + + // Send confirmation byte back to the host + WriteNextResponseByte('\r'); + } + else if (Command == 'p') + { + // Indicate serial programmer back to the host + WriteNextResponseByte('S'); + } + else if (Command == 'S') + { + // Write the 7-byte software identifier to the endpoint + for (uint8_t CurrByte = 0; CurrByte < 7; CurrByte++) + WriteNextResponseByte(SOFTWARE_IDENTIFIER[CurrByte]); + } + else if (Command == 'V') + { + WriteNextResponseByte('0' + BOOTLOADER_VERSION_MAJOR); + WriteNextResponseByte('0' + BOOTLOADER_VERSION_MINOR); + } + else if (Command == 's') + { + WriteNextResponseByte(AVR_SIGNATURE_3); + WriteNextResponseByte(AVR_SIGNATURE_2); + WriteNextResponseByte(AVR_SIGNATURE_1); + } + else if (Command == 'e') + { + // Clear the application section of flash + for (uint32_t CurrFlashAddress = 0; CurrFlashAddress < BOOT_START_ADDR; CurrFlashAddress += SPM_PAGESIZE) + { + boot_page_erase(CurrFlashAddress); + boot_spm_busy_wait(); + boot_page_write(CurrFlashAddress); + boot_spm_busy_wait(); + } + + // Send confirmation byte back to the host + WriteNextResponseByte('\r'); + } + #if !defined(NO_LOCK_BYTE_WRITE_SUPPORT) + else if (Command == 'l') + { + // Set the lock bits to those given by the host + boot_lock_bits_set(FetchNextCommandByte()); + + // Send confirmation byte back to the host + WriteNextResponseByte('\r'); + } + #endif + else if (Command == 'r') + { + WriteNextResponseByte(boot_lock_fuse_bits_get(GET_LOCK_BITS)); + } + else if (Command == 'F') + { + WriteNextResponseByte(boot_lock_fuse_bits_get(GET_LOW_FUSE_BITS)); + } + else if (Command == 'N') + { + WriteNextResponseByte(boot_lock_fuse_bits_get(GET_HIGH_FUSE_BITS)); + } + else if (Command == 'Q') + { + WriteNextResponseByte(boot_lock_fuse_bits_get(GET_EXTENDED_FUSE_BITS)); + } + #if !defined(NO_BLOCK_SUPPORT) + else if (Command == 'b') + { + WriteNextResponseByte('Y'); + + // Send block size to the host + WriteNextResponseByte(SPM_PAGESIZE >> 8); + WriteNextResponseByte(SPM_PAGESIZE & 0xFF); + } + else if ((Command == 'B') || (Command == 'g')) + { + // Keep resetting the timeout counter if we're receiving self-programming instructions + Timeout = 0; + // Delegate the block write/read to a separate function for clarity + ReadWriteMemoryBlock(Command); + } + #endif + #if !defined(NO_FLASH_BYTE_SUPPORT) + else if (Command == 'C') + { + // Write the high byte to the current flash page + boot_page_fill(CurrAddress, FetchNextCommandByte()); + + // Send confirmation byte back to the host + WriteNextResponseByte('\r'); + } + else if (Command == 'c') + { + // Write the low byte to the current flash page + boot_page_fill(CurrAddress | 0x01, FetchNextCommandByte()); + + // Increment the address + CurrAddress += 2; + + // Send confirmation byte back to the host + WriteNextResponseByte('\r'); + } + else if (Command == 'm') + { + // Commit the flash page to memory + boot_page_write(CurrAddress); + + // Wait until write operation has completed + boot_spm_busy_wait(); + + // Send confirmation byte back to the host + WriteNextResponseByte('\r'); + } + else if (Command == 'R') + { + #if (FLASHEND > 0xFFFF) + uint16_t ProgramWord = pgm_read_word_far(CurrAddress); + #else + uint16_t ProgramWord = pgm_read_word(CurrAddress); + #endif + + WriteNextResponseByte(ProgramWord >> 8); + WriteNextResponseByte(ProgramWord & 0xFF); + } + #endif + #if !defined(NO_EEPROM_BYTE_SUPPORT) + else if (Command == 'D') + { + // Read the byte from the endpoint and write it to the EEPROM + eeprom_write_byte((uint8_t*)((intptr_t)(CurrAddress >> 1)), FetchNextCommandByte()); + + // Increment the address after use + CurrAddress += 2; + + // Send confirmation byte back to the host + WriteNextResponseByte('\r'); + } + else if (Command == 'd') + { + // Read the EEPROM byte and write it to the endpoint + WriteNextResponseByte(eeprom_read_byte((uint8_t*)((intptr_t)(CurrAddress >> 1)))); + + // Increment the address after use + CurrAddress += 2; + } + #endif + else if (Command != 27) + { + // Unknown (non-sync) command, return fail code + WriteNextResponseByte('?'); + } + + + /* Select the IN endpoint */ + Endpoint_SelectEndpoint(CDC_TX_EPNUM); + + /* Remember if the endpoint is completely full before clearing it */ + bool IsEndpointFull = !(Endpoint_IsReadWriteAllowed()); + + /* Send the endpoint data to the host */ + Endpoint_ClearIN(); + + /* If a full endpoint's worth of data was sent, we need to send an empty packet afterwards to signal end of transfer */ + if (IsEndpointFull) + { + while (!(Endpoint_IsINReady())) + { + if (USB_DeviceState == DEVICE_STATE_Unattached) + return; + } + + Endpoint_ClearIN(); + } + + /* Wait until the data has been sent to the host */ + while (!(Endpoint_IsINReady())) + { + if (USB_DeviceState == DEVICE_STATE_Unattached) + return; + } + + /* Select the OUT endpoint */ + Endpoint_SelectEndpoint(CDC_RX_EPNUM); + + /* Acknowledge the command from the host */ + Endpoint_ClearOUT(); +} + -- cgit v1.2.3-18-g5258