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Version 7.0

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(Finally) commit the MarkG55/majekw mcusr patches.
Optimize a bit by implementing a union for the
 various 16bit address values used (based on
 observation by "aweatherguy", but different.)
Slightly optimize math in VIRTUAL_BOOT code
Add some virboot targets, fix some fuses.
Implement LED_START_ON; less code than flashes

"atmega328 SUPPORT_EEPROM=1 LED_START_FLASHES=0 LED_START_ON=1"
now fits (barely) in 512 bytes.
This commit is contained in:
WestfW
2018-07-24 00:40:48 -07:00
parent 9e7396e1f9
commit a50f47b8ac
2 changed files with 148 additions and 67 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
optiboot/bootloaders/optiboot/Makefile
View File

@@ -158,6 +158,11 @@ else
LED_START_FLASHES_CMD = -DLED_START_FLASHES=3 LED_START_FLASHES_CMD = -DLED_START_FLASHES=3
endif endif
ifdef LED_START_ON
LED_START_ON_CMD = -DLED_START_ON=1
dummy = FORCE
endif
# BIG_BOOT: Include extra features, up to 1K. # BIG_BOOT: Include extra features, up to 1K.
ifdef BIGBOOT ifdef BIGBOOT
BIGBOOT_CMD = -DBIGBOOT=1 BIGBOOT_CMD = -DBIGBOOT=1
@@ -185,7 +190,7 @@ endif
COMMON_OPTIONS = $(BAUD_RATE_CMD) $(LED_START_FLASHES_CMD) $(BIGBOOT_CMD) COMMON_OPTIONS = $(BAUD_RATE_CMD) $(LED_START_FLASHES_CMD) $(BIGBOOT_CMD)
COMMON_OPTIONS += $(SOFT_UART_CMD) $(LED_DATA_FLASH_CMD) $(LED_CMD) $(SS_CMD) COMMON_OPTIONS += $(SOFT_UART_CMD) $(LED_DATA_FLASH_CMD) $(LED_CMD) $(SS_CMD)
COMMON_OPTIONS += $(SUPPORT_EEPROM_CMD) COMMON_OPTIONS += $(SUPPORT_EEPROM_CMD) $(LED_START_ON_CMD)
#UART is handled separately and only passed for devices with more than one. #UART is handled separately and only passed for devices with more than one.
ifdef UART ifdef UART
@@ -279,7 +284,12 @@ virboot8_isp: isp
atmega168: TARGET = atmega168 atmega168: TARGET = atmega168
atmega168: MCU_TARGET = atmega168 atmega168: MCU_TARGET = atmega168
atmega168: CFLAGS += $(COMMON_OPTIONS) atmega168: CFLAGS += $(COMMON_OPTIONS)
atmega168: AVR_FREQ ?= 16000000L atmega168: AVR_FREQ ?= 16000000L
ifndef BIGBOOT
atmega168: LDSECTIONS = -Wl,--section-start=.text=0x3e00 -Wl,--section-start=.version=0x3ffe
else
atmeg168: LDSECTIONS = -Wl,--section-start=.text=0x3c00 -Wl,--section-start=.version=0x3ffe
endif
atmega168: $(PROGRAM)_atmega168.hex atmega168: $(PROGRAM)_atmega168.hex
atmega168: $(PROGRAM)_atmega168.lst atmega168: $(PROGRAM)_atmega168.lst
@@ -289,8 +299,13 @@ atmega168_isp: TARGET = atmega168
atmega168_isp: HFUSE ?= DD atmega168_isp: HFUSE ?= DD
# Full swing (16MHz) 16KCK/14CK+65ms # Full swing (16MHz) 16KCK/14CK+65ms
atmega168_isp: LFUSE ?= F7 atmega168_isp: LFUSE ?= F7
ifndef BIGBOOT
# 512 byte boot # 512 byte boot
atmega168_isp: EFUSE ?= 04 atmega168_isp: EFUSE ?= 04
else
# 1024byte boot
atmega168_isp: EFUSE ?= FA
endif
atmega168_isp: isp atmega168_isp: isp
atmega16: TARGET = atmega16 atmega16: TARGET = atmega16
@@ -344,15 +359,24 @@ atmega8: TARGET = atmega8
atmega8: MCU_TARGET = atmega8 atmega8: MCU_TARGET = atmega8
atmega8: CFLAGS += $(COMMON_OPTIONS) atmega8: CFLAGS += $(COMMON_OPTIONS)
atmega8: AVR_FREQ ?= 16000000L atmega8: AVR_FREQ ?= 16000000L
ifndef BIGBOOT
atmega8: LDSECTIONS = -Wl,--section-start=.text=0x1e00 -Wl,--section-start=.version=0x1ffe -Wl,--gc-sections -Wl,--undefined=optiboot_version atmega8: LDSECTIONS = -Wl,--section-start=.text=0x1e00 -Wl,--section-start=.version=0x1ffe -Wl,--gc-sections -Wl,--undefined=optiboot_version
else
atmega8: LDSECTIONS = -Wl,--section-start=.text=0x1c00 -Wl,--section-start=.version=0x1ffe -Wl,--gc-sections -Wl,--undefined=optiboot_version
endif
atmega8: $(PROGRAM)_atmega8.hex atmega8: $(PROGRAM)_atmega8.hex
atmega8: $(PROGRAM)_atmega8.lst atmega8: $(PROGRAM)_atmega8.lst
atmega8_isp: atmega8 atmega8_isp: atmega8
atmega8_isp: TARGET = atmega8 atmega8_isp: TARGET = atmega8
atmega8_isp: MCU_TARGET = atmega8 atmega8_isp: MCU_TARGET = atmega8
ifndef BIGBOOT
# SPIEN, CKOPT (for full swing xtal), Bootsize=512B # SPIEN, CKOPT (for full swing xtal), Bootsize=512B
atmega8_isp: HFUSE ?= CC atmega8_isp: HFUSE ?= CC
else
# SPIEN, CKOPT (for full swing xtal), Bootsize=1024B
atmega8_isp: HFUSE ?= CA
endif
# 2.7V brownout, 16MHz Xtal, 16KCK/14CK+65ms # 2.7V brownout, 16MHz Xtal, 16KCK/14CK+65ms
atmega8_isp: LFUSE ?= BF atmega8_isp: LFUSE ?= BF
atmega8_isp: isp atmega8_isp: isp

187
optiboot/bootloaders/optiboot/optiboot.c
View File

@@ -154,6 +154,18 @@
/**********************************************************/ /**********************************************************/
/* Edit History: */ /* Edit History: */
/* */ /* */
/* July 2018 */
/* 7.0 WestfW (with much input from Others) */
/* Fix MCUSR treatement as per much discussion, */
/* Patches by MarkG55, makjekw. Preserve value */
/* for the application, as much as possible. */
/* see https://github.com/Optiboot/optiboot/issues/97 */
/* Optimize a bit by implementing a union for the */
/* various 16bit address values used (based on */
/* observation by "aweatherguy", but different.) */
/* Slightly optimize math in VIRTUAL_BOOT code */
/* Add some virboot targets, fix some fuses. */
/* Implement LED_START_ON; less code than flashes */
/* Aug 2014 */ /* Aug 2014 */
/* 6.2 WestfW: make size of length variables dependent */ /* 6.2 WestfW: make size of length variables dependent */
/* on the SPM_PAGESIZE. This saves space */ /* on the SPM_PAGESIZE. This saves space */
@@ -224,8 +236,8 @@
/* 4.1 WestfW: put version number in binary. */ /* 4.1 WestfW: put version number in binary. */
/**********************************************************/ /**********************************************************/
#define OPTIBOOT_MAJVER 6 #define OPTIBOOT_MAJVER 7
#define OPTIBOOT_MINVER 2 #define OPTIBOOT_MINVER 0
/* /*
* OPTIBOOT_CUSTOMVER should be defined (by the makefile) for custom edits * OPTIBOOT_CUSTOMVER should be defined (by the makefile) for custom edits
@@ -246,6 +258,20 @@ optiboot_version = 256*(OPTIBOOT_MAJVER + OPTIBOOT_CUSTOMVER) + OPTIBOOT_MINVER;
#include <avr/pgmspace.h> #include <avr/pgmspace.h>
#include <avr/eeprom.h> #include <avr/eeprom.h>
/*
* optiboot uses several "address" variables that are sometimes byte pointers,
* sometimes word pointers. sometimes 16bit quantities, and sometimes built
* up from 8bit input characters. avr-gcc is not great at optimizing the
* assembly of larger words from bytes, but we can use the usual union to
* do this manually. Expanding it a little, we can also get rid of casts.
*/
typedef union {
uint8_t *bptr;
uint16_t *wptr;
uint16_t word;
uint8_t bytes[2];
} addr16_t;
/* /*
* Note that we use our own version of "boot.h" * Note that we use our own version of "boot.h"
* <avr/boot.h> uses sts instructions, but this version uses out instructions * <avr/boot.h> uses sts instructions, but this version uses out instructions
@@ -364,10 +390,10 @@ static inline void getNch(uint8_t);
static inline void flash_led(uint8_t); static inline void flash_led(uint8_t);
#endif #endif
static inline void watchdogReset(); static inline void watchdogReset();
static inline void writebuffer(int8_t memtype, uint8_t *mybuff, static inline void writebuffer(int8_t memtype, addr16_t mybuff,
uint16_t address, pagelen_t len); addr16_t address, pagelen_t len);
static inline void read_mem(uint8_t memtype, static inline void read_mem(uint8_t memtype,
uint16_t address, pagelen_t len); addr16_t, pagelen_t len);
#ifdef SOFT_UART #ifdef SOFT_UART
void uartDelay() __attribute__ ((naked)); void uartDelay() __attribute__ ((naked));
@@ -394,7 +420,7 @@ void appStart(uint8_t rstFlags) __attribute__ ((naked));
/* C zero initialises all global variables. However, that requires */ /* C zero initialises all global variables. However, that requires */
/* These definitions are NOT zero initialised, but that doesn't matter */ /* These definitions are NOT zero initialised, but that doesn't matter */
/* This allows us to drop the zero init code, saving us memory */ /* This allows us to drop the zero init code, saving us memory */
#define buff ((uint8_t*)(RAMSTART)) static addr16_t buff = {(uint8_t *)(RAMSTART)};
/* Virtual boot partition support */ /* Virtual boot partition support */
#ifdef VIRTUAL_BOOT_PARTITION #ifdef VIRTUAL_BOOT_PARTITION
@@ -454,7 +480,7 @@ int main(void) {
* (initializing address keeps the compiler happy, but isn't really * (initializing address keeps the compiler happy, but isn't really
* necessary, and uses 4 bytes of flash.) * necessary, and uses 4 bytes of flash.)
*/ */
register uint16_t address = 0; register addr16_t address;
register pagelen_t length; register pagelen_t length;
// After the zero init loop, this is the first code to run. // After the zero init loop, this is the first code to run.
@@ -472,20 +498,48 @@ int main(void) {
#endif #endif
/* /*
* modified Adaboot no-wait mod. * Protect as much from MCUSR as possible for application
* Pass the reset reason to app. Also, it appears that an Uno poweron * and still skip bootloader if not necessary
* can leave multiple reset flags set; we only want the bootloader to *
* run on an 'external reset only' status * Code by MarkG55
* see discusion in https://github.com/Optiboot/optiboot/issues/97
*/ */
#if !defined(__AVR_ATmega16__) #if !defined(__AVR_ATmega16__)
ch = MCUSR; ch = MCUSR;
MCUSR = 0;
#else #else
ch = MCUCSR; ch = MCUCSR;
MCUCSR = 0;
#endif #endif
if (ch & (_BV(WDRF) | _BV(BORF) | _BV(PORF))) // Skip all logic and run bootloader if MCUSR is cleared (application request)
appStart(ch); if (ch != 0) {
/*
* To run the boot loader, External Reset Flag must be set.
* If not, we could make shortcut and jump directly to application code.
* Also WDRF set with EXTRF is a result of Optiboot timeout, so we
* shouldn't run bootloader in loop :-) That's why:
* 1. application is running if WDRF is cleared
* 2. we clear WDRF if it's set with EXTRF to avoid loops
* One problematic scenario: broken application code sets watchdog timer
* without clearing MCUSR before and triggers it quickly. But it's
* recoverable by power-on with pushed reset button.
*/
if ((ch & (_BV(WDRF) | _BV(EXTRF))) != _BV(EXTRF)) {
if (ch & _BV(EXTRF)) {
/*
* Clear WDRF because it was most probably set by wdr in bootloader.
* It's also needed to avoid loop by broken application which could
* prevent entering bootloader.
* '&' operation is skipped to spare few bytes as bits in MCUSR
* can only be cleared.
*/
#if !defined(__AVR_ATmega16__)
MCUSR = ~(_BV(WDRF));
#else
MCUCSR = ~(_BV(WDRF));
#endif
}
appStart(ch);
}
}
#if LED_START_FLASHES > 0 #if LED_START_FLASHES > 0
// Set up Timer 1 for timeout counter // Set up Timer 1 for timeout counter
@@ -509,7 +563,7 @@ int main(void) {
// Set up watchdog to trigger after 1s // Set up watchdog to trigger after 1s
watchdogConfig(WATCHDOG_1S); watchdogConfig(WATCHDOG_1S);
#if (LED_START_FLASHES > 0) || defined(LED_DATA_FLASH) #if (LED_START_FLASHES > 0) || defined(LED_DATA_FLASH) || defined(LED_START_ON)
/* Set LED pin as output */ /* Set LED pin as output */
LED_DDR |= _BV(LED); LED_DDR |= _BV(LED);
#endif #endif
@@ -522,6 +576,11 @@ int main(void) {
#if LED_START_FLASHES > 0 #if LED_START_FLASHES > 0
/* Flash onboard LED to signal entering of bootloader */ /* Flash onboard LED to signal entering of bootloader */
flash_led(LED_START_FLASHES * 2); flash_led(LED_START_FLASHES * 2);
#else
#if defined(LED_START_ON)
/* Turn on LED to indicate starting bootloader (less code!) */
LED_PORT |= _BV(LED);
#endif
#endif #endif
/* Forever loop: exits by causing WDT reset */ /* Forever loop: exits by causing WDT reset */
@@ -558,20 +617,18 @@ int main(void) {
} }
else if(ch == STK_LOAD_ADDRESS) { else if(ch == STK_LOAD_ADDRESS) {
// LOAD ADDRESS // LOAD ADDRESS
uint16_t newAddress; address.bytes[0] = getch();
newAddress = getch(); address.bytes[1] = getch();
newAddress = (newAddress & 0xff) | (getch() << 8);
#ifdef RAMPZ #ifdef RAMPZ
// Transfer top bit to LSB in RAMPZ // Transfer top bit to LSB in RAMPZ
if (newAddress & 0x8000) { if (address.bytes[1] & 0x80) {
RAMPZ |= 0x01; RAMPZ |= 0x01;
} }
else { else {
RAMPZ &= 0xFE; RAMPZ &= 0xFE;
} }
#endif #endif
newAddress += newAddress; // Convert from word address to byte address address.word *= 2; // Convert from word address to byte address
address = newAddress;
verifySpace(); verifySpace();
} }
else if(ch == STK_UNIVERSAL) { else if(ch == STK_UNIVERSAL) {
@@ -608,7 +665,7 @@ int main(void) {
desttype = getch(); desttype = getch();
// read a page worth of contents // read a page worth of contents
bufPtr = buff; bufPtr = buff.bptr;
do *bufPtr++ = getch(); do *bufPtr++ = getch();
while (--length); while (--length);
@@ -621,51 +678,55 @@ int main(void) {
* AVR with 4-byte ISR Vectors and "jmp" * AVR with 4-byte ISR Vectors and "jmp"
* WARNING: this works only up to 128KB flash! * WARNING: this works only up to 128KB flash!
*/ */
if (address == 0) { if (address.word == 0) {
// This is the reset vector page. We need to live-patch the // This is the reset vector page. We need to live-patch the
// code so the bootloader runs first. // code so the bootloader runs first.
// //
// Save jmp targets (for "Verify") // Save jmp targets (for "Verify")
rstVect0_sav = buff[rstVect0]; rstVect0_sav = buff.bptr[rstVect0];
rstVect1_sav = buff[rstVect1]; rstVect1_sav = buff.bptr[rstVect1];
saveVect0_sav = buff[saveVect0]; saveVect0_sav = buff.bptr[saveVect0];
saveVect1_sav = buff[saveVect1]; saveVect1_sav = buff.bptr[saveVect1];
// Move RESET jmp target to 'save' vector // Move RESET jmp target to 'save' vector
buff[saveVect0] = rstVect0_sav; buff.bptr[saveVect0] = rstVect0_sav;
buff[saveVect1] = rstVect1_sav; buff.bptr[saveVect1] = rstVect1_sav;
// Add jump to bootloader at RESET vector // Add jump to bootloader at RESET vector
// WARNING: this works as long as 'main' is in first section // WARNING: this works as long as 'main' is in first section
buff[rstVect0] = ((uint16_t)main) & 0xFF; buff.bptr[rstVect0] = ((uint16_t)main) & 0xFF;
buff[rstVect1] = ((uint16_t)main) >> 8; buff.bptr[rstVect1] = ((uint16_t)main) >> 8;
} }
#else #else
/* /*
* AVR with 2-byte ISR Vectors and rjmp * AVR with 2-byte ISR Vectors and rjmp
*/ */
if ((uint16_t)(void*)address == rstVect0) { if (address.word == rstVect0) {
// This is the reset vector page. We need to live-patch // This is the reset vector page. We need to live-patch
// the code so the bootloader runs first. // the code so the bootloader runs first.
// //
// Move RESET vector to 'save' vector // Move RESET vector to 'save' vector
// Save jmp targets (for "Verify") // Save jmp targets (for "Verify")
rstVect0_sav = buff[rstVect0]; rstVect0_sav = buff.bptr[rstVect0];
rstVect1_sav = buff[rstVect1]; rstVect1_sav = buff.bptr[rstVect1];
saveVect0_sav = buff[saveVect0]; saveVect0_sav = buff.bptr[saveVect0];
saveVect1_sav = buff[saveVect1]; saveVect1_sav = buff.bptr[saveVect1];
// Instruction is a relative jump (rjmp), so recalculate. // Instruction is a relative jump (rjmp), so recalculate.
uint16_t vect=(rstVect0_sav & 0xff) | ((rstVect1_sav & 0x0f)<<8); //calculate 12b displacement // an RJMP instruction is 0b1100xxxx xxxxxxxx, so we should be able to
vect = (vect-save_vect_num) & 0x0fff; //substract 'save' interrupt position and wrap around 4096 // do math on the offsets without masking it off first.
addr16_t vect;
vect.bytes[0] = rstVect0_sav;
vect.bytes[1] = rstVect1_sav;
vect.word = (vect.word-save_vect_num); //substract 'save' interrupt position
// Move RESET jmp target to 'save' vector // Move RESET jmp target to 'save' vector
buff[saveVect0] = vect & 0xff; buff.bptr[saveVect0] = vect.bytes[0];
buff[saveVect1] = (vect >> 8) | 0xc0; // buff.bptr[saveVect1] = (vect.bytes[1] & 0x0F)| 0xC0; // make an "rjmp"
// Add rjump to bootloader at RESET vector // Add rjump to bootloader at RESET vector
vect = ((uint16_t)main) &0x0fff; //WARNIG: this works as long as 'main' is in first section vect.word = ((uint16_t)main); // (main) is always <= 0x0FFF; no masking needed.
buff[0] = vect & 0xFF; // rjmp 0x1c00 instruction buff.bptr[0] = vect.bytes[0]; // rjmp 0x1c00 instruction
buff[1] = (vect >> 8) | 0xC0; buff.bptr[1] = vect.bytes[1] | 0xC0; // make an "rjmp"
} }
#endif // FLASHEND #endif // FLASHEND
#endif // VBP #endif // VBP
@@ -883,14 +944,14 @@ void appStart(uint8_t rstFlags) {
/* /*
* void writebuffer(memtype, buffer, address, length) * void writebuffer(memtype, buffer, address, length)
*/ */
static inline void writebuffer(int8_t memtype, uint8_t *mybuff, static inline void writebuffer(int8_t memtype, addr16_t mybuff,
uint16_t address, pagelen_t len) addr16_t address, pagelen_t len)
{ {
switch (memtype) { switch (memtype) {
case 'E': // EEPROM case 'E': // EEPROM
#if defined(SUPPORT_EEPROM) || defined(BIGBOOT) #if defined(SUPPORT_EEPROM) || defined(BIGBOOT)
while(len--) { while(len--) {
eeprom_write_byte((uint8_t *)(address++), *mybuff++); eeprom_write_byte((address.bptr++), *(mybuff.bptr++));
} }
#else #else
/* /*
@@ -910,8 +971,7 @@ static inline void writebuffer(int8_t memtype, uint8_t *mybuff,
*/ */
{ {
// Copy buffer into programming buffer // Copy buffer into programming buffer
uint8_t *bufPtr = mybuff; uint16_t addrPtr = address.word;
uint16_t addrPtr = (uint16_t)(void*)address;
/* /*
* Start the page erase and wait for it to finish. There * Start the page erase and wait for it to finish. There
@@ -919,24 +979,21 @@ static inline void writebuffer(int8_t memtype, uint8_t *mybuff,
* the serial link, but the performance improvement was slight, * the serial link, but the performance improvement was slight,
* and we needed the space back. * and we needed the space back.
*/ */
__boot_page_erase_short((uint16_t)(void*)address); __boot_page_erase_short(address.word);
boot_spm_busy_wait(); boot_spm_busy_wait();
/* /*
* Copy data from the buffer into the flash write buffer. * Copy data from the buffer into the flash write buffer.
*/ */
do { do {
uint16_t a; __boot_page_fill_short((uint16_t)(void*)addrPtr, *(mybuff.wptr++));
a = *bufPtr++;
a |= (*bufPtr++) << 8;
__boot_page_fill_short((uint16_t)(void*)addrPtr,a);
addrPtr += 2; addrPtr += 2;
} while (len -= 2); } while (len -= 2);
/* /*
* Actually Write the buffer to flash (and wait for it to finish.) * Actually Write the buffer to flash (and wait for it to finish.)
*/ */
__boot_page_write_short((uint16_t)(void*)address); __boot_page_write_short(address.word);
boot_spm_busy_wait(); boot_spm_busy_wait();
#if defined(RWWSRE) #if defined(RWWSRE)
// Reenable read access to flash // Reenable read access to flash
@@ -947,7 +1004,7 @@ static inline void writebuffer(int8_t memtype, uint8_t *mybuff,
} // switch } // switch
} }
static inline void read_mem(uint8_t memtype, uint16_t address, pagelen_t length) static inline void read_mem(uint8_t memtype, addr16_t address, pagelen_t length)
{ {
uint8_t ch; uint8_t ch;
@@ -956,7 +1013,7 @@ static inline void read_mem(uint8_t memtype, uint16_t address, pagelen_t length)
#if defined(SUPPORT_EEPROM) || defined(BIGBOOT) #if defined(SUPPORT_EEPROM) || defined(BIGBOOT)
case 'E': // EEPROM case 'E': // EEPROM
do { do {
putch(eeprom_read_byte((uint8_t *)(address++))); putch(eeprom_read_byte((address.bptr++)));
} while (--length); } while (--length);
break; break;
#endif #endif
@@ -964,22 +1021,22 @@ static inline void read_mem(uint8_t memtype, uint16_t address, pagelen_t length)
do { do {
#ifdef VIRTUAL_BOOT_PARTITION #ifdef VIRTUAL_BOOT_PARTITION
// Undo vector patch in bottom page so verify passes // Undo vector patch in bottom page so verify passes
if (address == rstVect0) ch = rstVect0_sav; if (address.word == rstVect0) ch = rstVect0_sav;
else if (address == rstVect1) ch = rstVect1_sav; else if (address.word == rstVect1) ch = rstVect1_sav;
else if (address == saveVect0) ch = saveVect0_sav; else if (address.word == saveVect0) ch = saveVect0_sav;
else if (address == saveVect1) ch = saveVect1_sav; else if (address.word == saveVect1) ch = saveVect1_sav;
else ch = pgm_read_byte_near(address); else ch = pgm_read_byte_near(address.bptr);
address++; address.bptr++;
#elif defined(RAMPZ) #elif defined(RAMPZ)
// Since RAMPZ should already be set, we need to use EPLM directly. // Since RAMPZ should already be set, we need to use EPLM directly.
// Also, we can use the autoincrement version of lpm to update "address" // Also, we can use the autoincrement version of lpm to update "address"
// do putch(pgm_read_byte_near(address++)); // do putch(pgm_read_byte_near(address++));
// while (--length); // while (--length);
// read a Flash and increment the address (may increment RAMPZ) // read a Flash and increment the address (may increment RAMPZ)
__asm__ ("elpm %0,Z+\n" : "=r" (ch), "=z" (address): "1" (address)); __asm__ ("elpm %0,Z+\n" : "=r" (ch), "=z" (address.bptr): "1" (address));
#else #else
// read a Flash byte and increment the address // read a Flash byte and increment the address
__asm__ ("lpm %0,Z+\n" : "=r" (ch), "=z" (address): "1" (address)); __asm__ ("lpm %0,Z+\n" : "=r" (ch), "=z" (address.bptr): "1" (address));
#endif #endif
putch(ch); putch(ch);
} while (--length); } while (--length);