Index: ram/ptdisp.c
===================================================================
--- ram/ptdisp.c	(revision ca867c1f50351a4f0c4d5dac3e213322ee739ea2)
+++ ram/ptdisp.c	(revision fe7b401f9f6952c804d05019fc19d1c4fade80b6)
@@ -71,5 +71,5 @@
 		/* row 0 */
 
-		memset(linbuf, '\261', 63);
+		memset(linbuf, (uint8_t)'\261', 63);
 		linbuf[0]  = '\272';
 		linbuf[48] = '\267';
@@ -104,5 +104,5 @@
 		/* row 18 */
 
-		memset(linbuf, '\261', 63);
+		memset(linbuf, (uint8_t)'\261', 63);
 		linbuf[0]  = '\266';
 		linbuf[48] = '\265';
@@ -117,5 +117,5 @@
 		/* row 24 */
 
-		memset(linbuf, '\261', 63);
+		memset(linbuf, (uint8_t)'\261', 63);
 		linbuf[0]  = '\271';
 		linbuf[62] = '\270';