diff --git a/libsrc/telestrat/read.s b/libsrc/telestrat/read.s
index 1d2315dce..736546363 100644
--- a/libsrc/telestrat/read.s
+++ b/libsrc/telestrat/read.s
@@ -33,11 +33,11 @@
         sec
         lda     PTR_READ_DEST
         sbc     ptr2
-        sta     tmp1
+        pha
         lda     PTR_READ_DEST+1
         sbc     ptr2+1
         tax
-        lda     tmp1
+        pla
 
         rts
 .endproc
diff --git a/libsrc/telestrat/write.s b/libsrc/telestrat/write.s
index 16bc64d69..37a896696 100644
--- a/libsrc/telestrat/write.s
+++ b/libsrc/telestrat/write.s
@@ -47,11 +47,11 @@ next:
         sec
         lda     PTR_READ_DEST
         sbc     ptr1
-        sta     tmp1
+        pha
         lda     PTR_READ_DEST+1
         sbc     ptr1+1
         tax
-        lda     tmp1
+        pla
         rts