diff --git a/Source/CPM3/bioskrnl.asm b/Source/CPM3/bioskrnl.asm
index 32e918b9..ab3a9ccd 100644
--- a/Source/CPM3/bioskrnl.asm
+++ b/Source/CPM3/bioskrnl.asm
@@ -244,7 +244,7 @@ co$next:
 	push h		; save the vector
 	push b		; save the count and character
 not$out$ready:
-	call coster ! ora a ! jz not$out$ready
+	push b ! call coster ! pop b ! ora a ! jz not$out$ready
 	pop b ! push b	; restore and resave the character and device
 	call ?co	; if device selected, print it
 	pop b		; recover count and character
diff --git a/Source/CPM3/boot.z80 b/Source/CPM3/boot.z80
index d0b5cb0f..47787569 100644
--- a/Source/CPM3/boot.z80
+++ b/Source/CPM3/boot.z80
@@ -667,4 +667,76 @@ drvtbladr	dw	@dtbl		; drive map address (filled in later)
 dphtbladr	dw	dph0		; dpb map address
 cbxsiz		equ	$ - cbx
 
+	if 0
+;
+; Print the hex word value in HL
+;
+phex16:
+	push	af
+	ld	a,h
+	call	phex8
+	ld	a,l
+	call	phex8
+	pop	af
+	ret
+;
+; Print the hex byte value in A
+;
+phex8:
+	push	af
+	push	de
+	call	hexascii
+	ld	a,d
+	call	cout
+	ld	a,e
+	call	cout
+	pop	de
+	pop	af
+	ret
+	
+;
+; Convert binary value in A to ascii hex characters in DE
+;
+hexascii:
+	ld	d,a
+	call	hexconv
+	ld	e,a
+	ld	a,d
+	rlca
+	rlca
+	rlca
+	rlca
+	call	hexconv
+	ld	d,a
+	ret
+;
+; convert low nibble of A to ascii hex
+;
+hexconv:
+	and	0fh	     ;low nibble only
+	add	a,90h
+	daa
+	adc	a,40h
+	daa
+	ret
+;
+; output character from A
+;
+cout:
+	; save all incoming registers
+	push	af
+	push	bc
+	push	de
+	push	hl
+	ld	e,a
+	ld	bc,0100h
+	rst	08
+	pop	hl
+	pop	de
+	pop	bc
+	pop	af
+	ret
+	
+	endif
+
 	end