diff --git a/ubb-patgen/ubb-patgen.c b/ubb-patgen/ubb-patgen.c
index 69edee4..af17e26 100644
--- a/ubb-patgen/ubb-patgen.c
+++ b/ubb-patgen/ubb-patgen.c
@@ -14,6 +14,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <unistd.h>
+#include <ctype.h>
 #include <string.h>
 #include <math.h>
 #include <time.h>
@@ -194,6 +195,45 @@ static void *parse_pattern(const char *s, int *nibbles)
 }
 
 
+static const char *load_pattern(const char *s)
+{
+	static char buf[20000]; /* more than enough :) */
+	FILE *file;
+	char *p = buf;
+	int comment = 0;
+	int c;
+
+	if (!strcmp(s, "-")) {
+		file = stdin;
+	} else {
+		file = fopen(s, "r");
+		if (!file)
+			return s;
+	}
+	while ((c = fgetc(file)) != EOF) {
+		if (comment) {
+			comment = c != '\n';
+			continue;
+		}
+		if (c == '#') {
+			comment = 1;
+			continue;
+		}
+		if (isspace(c))
+			continue;
+		if (buf+sizeof(buf)-1 == p) {
+			fprintf(stderr, "%s: file is too big\n", s);
+			exit(1);
+		}
+		*p++ = c;
+	}
+	if (file != stdin)
+		fclose(file);
+	*p = 0;
+	return buf;
+}
+
+
 /* ----- DMA control ------------------------------------------------------- */
 
 
@@ -449,7 +489,7 @@ static void usage(const char *name)
 "usage: %s\n"
 "       %s [-q] -f freq_hz\n"
 "       %s [-q] [-f freq_hz] -c [active_s]\n"
-"       %s [-q] [-f freq_hz] [-C] pattern\n\n"
+"       %s [-q] [-f freq_hz] [-C] file|pattern\n\n"
 "  -c          output bus clock on CLK without sending a pattern\n"
 "  -C          temporarily output bus clock on CLK (for debugging)\n"
 "  -f freq_hz  set bus clock to the specified frequency (default: 1 MHz)\n"
@@ -457,6 +497,7 @@ static void usage(const char *name)
 "              differences.\n\n"
 "  active_s    keep running that many seconds after setting the clock\n"
 "              (default: exit immediately but leave the clock on)\n"
+"  file        file containing the pattern\n"
 "  pattern     send the specified pattern on DAT0 through DAT3\n\n"
 "Frequency: the frequency in Hz, optionally followed by \"M\" or \"k\",\n"
 "  optionally followed by \"Hz\", optionally followed by \"+\" or \"-\".\n"
@@ -538,6 +579,9 @@ int main(int argc, char **argv)
 		usage(*argv);
 	}
 
+	if (pattern)
+		pattern = load_pattern(pattern);
+
 	ubb_open(UBB_ALL);
 
 	PDFUNS = UBB_CMD;