From aed4bfdb5bf773c850581509d582a281aec4fd59 Mon Sep 17 00:00:00 2001
From: Michael Moon <triffid.hunter@gmail.com>
Date: Sat, 30 Aug 2014 19:23:54 +1000
Subject: [PATCH] Canned G-code: implement continuous replay of G-code stored
 on flash.

---
 Makefile-common | 12 ++++++++++--
 canned_gcode.g  |  3 +++
 canned_gcode.h  |  3 +++
 mendel.c        | 38 +++++++++++++++++++++++++++++++++++---
 4 files changed, 51 insertions(+), 5 deletions(-)
 create mode 100644 canned_gcode.g
 create mode 100644 canned_gcode.h

diff --git a/Makefile-common b/Makefile-common
index 15c67e6..31cd81b 100644
--- a/Makefile-common
+++ b/Makefile-common
@@ -49,7 +49,7 @@ OBJDUMP = $(TOOLCHAIN)objdump
 OBJCOPY = $(TOOLCHAIN)objcopy
 
 
-OBJ = $(patsubst %.c,$(BUILDDIR)/%.o,$(SOURCES))
+OBJ = $(patsubst %.c,$(BUILDDIR)/%.o,$(SOURCES)) $(BUILDDIR)/canned_gcode.o
 
 .PHONY: all clean doc functionsbysize
 .PRECIOUS: %.o %.elf
@@ -57,7 +57,7 @@ OBJ = $(patsubst %.c,$(BUILDDIR)/%.o,$(SOURCES))
 all: $(BUILDDIR) $(TARGET)
 
 clean:
-	rm -rf $(BUILDDIR) $(TARGET) *~
+	rm -rf $(BUILDDIR) $(TARGET) *~ canned_gcode.c
 
 doc: Doxyfile *.c *.h
 	doxygen $<
@@ -107,3 +107,11 @@ $(BUILDDIR)/%.bin: $(BUILDDIR)/%.elf
 $(BUILDDIR)/%.sym: $(BUILDDIR)/%.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 > $@
+
+canned_gcode.c: canned_gcode.g
+	@echo "  GEN       $@"
+	@echo "#include \"canned_gcode.h\"" > $@
+	@echo "" >> $@
+	@echo -n "const char canned_gcode_P[] PROGMEM = \"" >> $@
+	@perl -pe 's/\n/\\n/gs' $< >> $@
+	@echo "\";" >> $@
diff --git a/canned_gcode.g b/canned_gcode.g
new file mode 100644
index 0000000..7605b24
--- /dev/null
+++ b/canned_gcode.g
@@ -0,0 +1,3 @@
+G28
+G1 X100
+G1 X0
diff --git a/canned_gcode.h b/canned_gcode.h
new file mode 100644
index 0000000..6942bc1
--- /dev/null
+++ b/canned_gcode.h
@@ -0,0 +1,3 @@
+#include <avr/pgmspace.h>
+
+extern const char canned_gcode_P[] PROGMEM;
diff --git a/mendel.c b/mendel.c
index 93ee06a..a78abfb 100644
--- a/mendel.c
+++ b/mendel.c
@@ -254,13 +254,45 @@ int main (void)
 #endif
 	init();
 
+  #ifdef CANNED_CYCLE
+    #include "canned_gcode.h"
+    uint32_t canned_gcode_pos = 0;
+  #endif /* CANNED_CYCLE */
+
 	// main loop
 	for (;;)
 	{
 		// if queue is full, no point in reading chars- host will just have to wait
-		if ((serial_rxchars() != 0) && (queue_full() == 0)) {
-			uint8_t c = serial_popchar();
-			gcode_parse_char(c);
+    if (queue_full() == 0) {
+      if (serial_rxchars() != 0) {
+        uint8_t c = serial_popchar();
+        gcode_parse_char(c);
+      }
+
+      #ifdef CANNED_CYCLE
+        /**
+          WARNING!
+
+          This code works on a per-character basis.
+
+          Any data received over serial WILL be randomly distributed through
+          the canned gcode, and you'll have a big mess!
+
+          The solution is to either store gcode parser state with each source,
+          or only parse a line at a time.
+
+          This will take extra ram, and may be out of scope for the Teacup
+          project.
+
+          If ever print-from-SD card is implemented, these changes may become
+          necessary.
+        */
+        if (pgm_read_byte(canned_gcode_P[++canned_gcode_pos]) == 0)
+          canned_gcode_pos = 0;
+        else
+          gcode_parse_char(pgm_read_byte(canned_gcode_P[canned_gcode_pos]));
+
+      #endif /* CANNED_CYCLE */
 		}
 
 		clock();