@@ -39,6 +39,5 @@
#define ESTABLISHED_TIMING2_BITS 0x08 /* Bit 3 -> 1024x768 @60 Hz */
#define HSYNC_POL 0
#define VSYNC_POL 0
-#define CRC 0x55
#include "edid.S"
@@ -39,6 +39,5 @@
/* No ESTABLISHED_TIMINGx_BITS */
#define HSYNC_POL 1
#define VSYNC_POL 1
-#define CRC 0xa0
#include "edid.S"
@@ -39,6 +39,5 @@
/* No ESTABLISHED_TIMINGx_BITS */
#define HSYNC_POL 1
#define VSYNC_POL 1
-#define CRC 0x9d
#include "edid.S"
@@ -39,6 +39,5 @@
/* No ESTABLISHED_TIMINGx_BITS */
#define HSYNC_POL 1
#define VSYNC_POL 1
-#define CRC 0x26
#include "edid.S"
@@ -39,6 +39,5 @@
/* No ESTABLISHED_TIMINGx_BITS */
#define HSYNC_POL 1
#define VSYNC_POL 1
-#define CRC 0x05
#include "edid.S"
@@ -36,6 +36,5 @@
#define ESTABLISHED_TIMING1_BITS 0x01 /* Bit 0: 800x600 @ 60Hz */
#define HSYNC_POL 1
#define VSYNC_POL 1
-#define CRC 0xc2
#include "edid.S"
@@ -47,12 +47,3 @@ EDID:
#define YBLANK vtotal-vdisp
#define YOFFSET vsyncstart-vdisp
#define YPULSE vsyncend-vsyncstart
-
-The CRC value in the last line
- #define CRC 0x55
-also is a bit tricky. After a first version of the binary data set is
-created, it must be checked with the "edid-decode" utility which will
-most probably complain about a wrong CRC. Fortunately, the utility also
-displays the correct CRC which must then be inserted into the source
-file. After the make procedure is repeated, the EDID data set is ready
-to be used.
@@ -15,10 +15,21 @@ clean:
%.o: %.S
@cc -c $^
-%.bin: %.o
+%.bin.nocrc: %.o
@objcopy -Obinary $^ $@
-%.bin.ihex: %.o
+%.crc: %.bin.nocrc
+ @list=$$(for i in `seq 1 127`; do head -c$$i $^ | tail -c1 \
+ | hexdump -v -e '/1 "%02X+"'; done); \
+ echo "ibase=16;100-($${list%?})%100" | bc >$@
+
+%.p: %.crc %.S
+ @cc -c -DCRC="$$(cat $*.crc)" -o $@ $*.S
+
+%.bin: %.p
+ @objcopy -Obinary $^ $@
+
+%.bin.ihex: %.p
@objcopy -Oihex $^ $@
@dos2unix $@ 2>/dev/null