diff --git a/sdtape.cpp b/sdtape.cpp
index 62f7e3e..d5524e1 100644
--- a/sdtape.cpp
+++ b/sdtape.cpp
@@ -6,6 +6,7 @@ static File file, dir;
 void sdtape::start(const char *programs)
 {
 	dir = SD.open(programs);
+	_pos = _len = 0;
 }
 
 void sdtape::stop()
diff --git a/spiram.cpp b/spiram.cpp
index 8c03739..843527d 100644
--- a/spiram.cpp
+++ b/spiram.cpp
@@ -20,18 +20,18 @@ spiram::operator byte()
 
 void spiram::checkpoint(Stream &s)
 {
-	char buf[Memory::page_size];
+	byte buf[Memory::page_size];
 	for (int i = 0; i < pages(); i++) {
 		spiRam.read_stream(i * 256, buf, sizeof(buf));
-		s.write((byte *)buf, sizeof(buf));
+		s.write(buf, sizeof(buf));
 	}
 }
 
 void spiram::restore(Stream &s)
 {
-	char buf[Memory::page_size];
+	byte buf[Memory::page_size];
 	for (int i = 0; i < pages(); i++) {
-		s.readBytes(buf, sizeof(buf));
+		s.readBytes((char *)buf, sizeof(buf));
 		spiRam.write_stream(i * 256, buf, sizeof(buf));
 	}
 }