diff options
Diffstat (limited to 'firmware/main.c')
| -rw-r--r-- | firmware/main.c | 32 |
1 files changed, 20 insertions, 12 deletions
diff --git a/firmware/main.c b/firmware/main.c index a2ed8b3..3d746af 100644 --- a/firmware/main.c +++ b/firmware/main.c @@ -9,7 +9,11 @@ * This Revision: $Id: main.c 786 2010-05-30 20:41:40Z cs $ */ -#define UBOOT_VERSION 1 +#define UBOOT_VERSION 2 +// how many milliseconds should host wait till it sends another erase or write? +// needs to be above 4.5 (and a whole integer) as avr freezes for 4.5ms +#define UBOOT_WRITE_SLEEP 8 + #include <avr/io.h> #include <avr/interrupt.h> @@ -25,10 +29,6 @@ static void leaveBootloader() __attribute__((__noreturn__)); #include "bootloaderconfig.h" #include "usbdrv/usbdrv.c" -// how many milliseconds should host wait till it sends another erase or write? -// needs to be above 4.5 (and a whole integer) as avr freezes for 4.5ms -#define UBOOT_WRITE_SLEEP 8 - /* ------------------------------------------------------------------------ */ #ifndef ulong @@ -67,18 +67,23 @@ static void leaveBootloader() __attribute__((__noreturn__)); // } longConverter_t; //////// Stuff Bluebie Added -#define PROGMEM_SIZE (BOOTLOADER_ADDRESS - 6) +// postscript are the few bytes at the end of programmable memory which store tinyVectors +// and used to in USBaspLoader-tiny85 store the checksum iirc +#define POSTSCRIPT_SIZE 6 /* maybe it could be 4 now we do not have checksums? */ +#define PROGMEM_SIZE (BOOTLOADER_ADDRESS - POSTSCRIPT_SIZE) /* max size of user program */ -// outstanding events for the mainloop to deal with +// events system schedules functions to run in the main loop static uchar events = 0; // bitmap of events to run #define EVENT_ERASE_APPLICATION 1 #define EVENT_WRITE_PAGE 2 #define EVENT_FINISH 4 +// controls state of events #define fireEvent(event) events |= (event) #define isEvent(event) (events & (event)) #define clearEvents() events = 0 +// length of bytes to write in to flash memory in upcomming usbFunctionWrite calls static uchar writeLength; // becomes 1 when some programming happened @@ -90,8 +95,8 @@ static uchar didWriteSomething = 0; -static uint16_t vectorTemp[2]; -static addr_t currentAddress; /* in bytes */ +static uint16_t vectorTemp[2]; // remember data to create tinyVector table before BOOTLOADER_ADDRESS +static addr_t currentAddress; // current progmem address, used for erasing and writing /* ------------------------------------------------------------------------ */ @@ -104,11 +109,14 @@ static uchar usbFunctionWrite(uchar *data, uchar length); static inline void initForUsbConnectivity(void); static inline void tiny85FlashInit(void); static inline void tiny85FlashWrites(void); +static inline void tiny85FinishWriting(void); static inline __attribute__((noreturn)) void leaveBootloader(void); - +// erase any existing application and write in jumps for usb interrupt and reset to bootloader +// - Because flash can be erased once and programmed several times, we can write the bootloader +// - vectors in now, and write in the application stuff around them later. +// - if vectors weren't written back in immidately, usb would fail. static inline void eraseApplication(void) { - // xxxxxx erase all pages starting from end of application section down to page 1 (leaving page 0) // erase all pages (every last one!) currentAddress = BOOTLOADER_ADDRESS; cli(); @@ -236,7 +244,7 @@ static uchar usbFunctionWrite(uchar *data, uchar length) { } // make sure we don't write over the bootloader! - if (currentAddress >= BOOTLOADER_ADDRESS - 6) { + if (currentAddress >= PROGMEM_SIZE) { __boot_page_fill_clear(); break; } |