Firmware/FiveD on Arduino

Rewrite of FiveD firmware for the atmega168-based Arduino by Triffid Hunter

• Blog Post
• Forum Thread
• Git Repository

This firmware is loosely based on the official FiveD Firmware, however it uses 100% integer math, and works very hard to minimize/eliminate long math operations in interrupt context.

Constant Acceleration

The official FiveD firmware changes speed by a fixed amount each step, however this also alters the step time. acceleration = dv/dt, so with a fixed dv but a changing dt, acceleration changes during a move. This makes high speeds quite unattainable as the acceleration quickly outstrips the motor's ability to keep up.

FiveD on Arduino contains a constant acceleration implementation.

Transmission of Multiple Commands

FiveD on Arduino has the capability to receive additional commands while working on the first one. This avoids short stops between commands and will allow for even more smooth transitions from one movement to the next in the future.

Patches, Enhancements

As Triffid Hunter is apparently out of town currently (2010-07-03), the Git Repository doesn't allow to upload patches and I don't want to do yet another fork, I'll upload patches here.

To apply those patches, type git apply in your terminal, inside your local copy of git repo, then copy the text given her into the terminal and hit ctrl-d. Well, I hope it works that way.

Make sources buildable with the Arduino IDE.

---
 mendel/mendel.pde |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
 create mode 100644 mendel/mendel.pde

diff --git a/mendel/mendel.pde b/mendel/mendel.pde
new file mode 100644
index 0000000..1c3f190
--- /dev/null
+++ b/mendel/mendel.pde
@@ -0,0 +1,4 @@
+
+/*
+	The existence of this file makes sources buildable with the Arduino IDE.
+*/
--

Achieve C89 compatibility, Arduino IDE's default.

---
 mendel/serial.c |   12 ++++++++----
 1 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/mendel/serial.c b/mendel/serial.c
index bce947b..767bdeb 100644
--- a/mendel/serial.c
+++ b/mendel/serial.c
@@ -146,7 +146,9 @@ void serial_writechar(uint8_t data)
 
 void serial_writeblock(void *data, int datalen)
 {
-	for (int i = 0; i < datalen; i++)
+	int i;
+
+	for (i = 0; i < datalen; i++)
 		serial_writechar(((uint8_t *) data)[i]);
 }
 
@@ -170,15 +172,17 @@ void serial_writechar_P(PGM_P data)
 
 void serial_writeblock_P(PGM_P data, int datalen)
 {
-	for (int i = 0; i < datalen; i++)
+	int i;
+
+	for (i = 0; i < datalen; i++)
 		serial_writechar_P(&data[i]);
 }
 
 void serial_writestr_P(PGM_P data)
 {
-	uint8_t i = 0;
+	uint8_t r, i = 0;
 	// yes, this is *supposed* to be assignment rather than comparison, so we break when r is assigned zero
-	for (uint8_t r; (r = pgm_read_byte(&data[i])); i++)
+	for (r; (r = pgm_read_byte(&data[i])); i++)
 		serial_writechar(r);
 }

--

RepRap host software expects a lowercase "ok" for confirmation.

---
 mendel/gcode.c |    4 ++++
 mendel/gcode.h |    3 +++
 2 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/mendel/gcode.c b/mendel/gcode.c
index 6d06e08..04a7e71 100644
--- a/mendel/gcode.c
+++ b/mendel/gcode.c
@@ -312,7 +312,11 @@ void scan_char(uint8_t c) {
 					) {
 					process_gcode_command(&next_target);
 
+					#ifdef	LOWERCASE_OK
+					serial_writestr_P(PSTR("ok\n"));
+					#else
 					serial_writestr_P(PSTR("OK\n"));
+					#endif
 
 					// expect next line number
 					next_target.N_expected++;
diff --git a/mendel/gcode.h b/mendel/gcode.h
index bfc9061..4805501 100644
--- a/mendel/gcode.h
+++ b/mendel/gcode.h
@@ -5,6 +5,9 @@
 
 #include	"dda.h"
 
+// host software expectations
+#define	LOWERCASE_OK
+
 // this is a very crude decimal-based floating point structure. a real floating point would at least have signed exponent
 typedef struct {
 	uint32_t	sign			:1;
--

Moved REQUIRE_LINENUMBER and REQUIRE_CHECKSUM #defines to gcode.h as well.

---
 mendel/Makefile |    4 +---
 mendel/gcode.h  |    2 ++
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/mendel/Makefile b/mendel/Makefile
index fcc78f6..3dfd4b6 100644
--- a/mendel/Makefile
+++ b/mendel/Makefile
@@ -38,8 +38,6 @@ OBJCOPY = $(ARCH)objcopy
 
 DEFS = -DF_CPU=$(F_CPU)
 # DEFS += "-DDEBUG=1"
-# DEFS += "-DREQUIRE_LINENUMBER"
-# DEFS += "-DREQUIRE_CHECKSUM"
 
 OPTIMIZE = -Os -ffunction-sections -finline-functions-called-once -DDEBUG
 # OPTIMIZE = -O0
@@ -103,4 +101,4 @@ size: $(PROGRAM).hex
 
 %.sym: %.elf
 	@echo "  SYM       $@"
-	@$(OBJDUMP) -t $< | perl -ne 'BEGIN { printf "  ADDR  NAME                  SIZE\n"; } /([0-9a-f]+)\s+(\w+)\s+O\s+\.(bss|data)\s+([0-9a-f]+)\s+(\w+)/ && printf "0x%04x  %-20s +%d\n", eval("0x$$1") & 0xFFFF, $$5, eval("0x$$4")' | sort -k1 > $@
\ No newline at end of file
+	@$(OBJDUMP) -t $< | perl -ne 'BEGIN { printf "  ADDR  NAME                  SIZE\n"; } /([0-9a-f]+)\s+(\w+)\s+O\s+\.(bss|data)\s+([0-9a-f]+)\s+(\w+)/ && printf "0x%04x  %-20s +%d\n", eval("0x$$1") & 0xFFFF, $$5, eval("0x$$4")' | sort -k1 > $@
diff --git a/mendel/gcode.h b/mendel/gcode.h
index 4805501..9fd1795 100644
--- a/mendel/gcode.h
+++ b/mendel/gcode.h
@@ -7,6 +7,8 @@
 
 // host software expectations
 #define	LOWERCASE_OK
+//#define	REQUIRE_LINENUMBER
+//#define	REQUIRE_CHECKSUM
 
 // this is a very crude decimal-based floating point structure. a real floating point would at least have signed exponent
 typedef struct {
--

An M-code stuck when receiving G commands and vice-versa.

Testcase:

M105
G1 F100

--> Temperatures would be sent the second time as well.

---
 mendel/gcode.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/mendel/gcode.c b/mendel/gcode.c
index 04a7e71..c05c598 100644
--- a/mendel/gcode.c
+++ b/mendel/gcode.c
@@ -335,7 +335,12 @@ void scan_char(uint8_t c) {
 		}
 
 		// reset variables
-		next_target.seen_X = next_target.seen_Y = next_target.seen_Z = next_target.seen_E = next_target.seen_F = next_target.seen_S = next_target.seen_P = next_target.seen_N = next_target.seen_checksum = next_target.seen_comment = next_target.checksum_read = next_target.checksum_calculated = 0;
+		next_target.seen_X = next_target.seen_Y = next_target.seen_Z = \
+			next_target.seen_E = next_target.seen_F = next_target.seen_G = \
+			next_target.seen_S = next_target.seen_P = next_target.seen_N = \
+			next_target.seen_M = next_target.seen_checksum = \
+			next_target.seen_comment = next_target.checksum_read = \
+			next_target.checksum_calculated = 0;
 		last_field = 0;
 		read_digit.sign = 0;
 		read_digit.mantissa = 0;
--