wait loop in powerup to very restart

Send the 0xF1 ack message
Wait a bit to see if we get it back. But don't wait forever.

Then reset the TipiService via cru pulse.

Then, wait for RCIN to be 0x00 before returning to console
powerup sequence.

hardware/dsr/Makefile

@@ -20,8 +20,11 @@ tipi.bin: $(sources) timestamp.gen
 timestamp.gen:
 	TIMESTAMP=`date --iso-8601="seconds"`; ( echo "	TEXT	\"$$TIMESTAMP\""; echo "	BYTE	0"; echo "	EVEN" ) >timestamp.gen
 
-.PHONY: burn 
+.PHONY: burn flash
 
 burn: tipi.bin
 	minipro -p "AM27C256@DIP28" -w tipi.bin -y
 
+flash: tipi.bin
+	minipro -p "AT29C256@DIP28" -w tipi.bin -y
+

hardware/dsr/powerup.a99

@@ -8,24 +8,39 @@ fbufheader
 	EVEN
 
 ; Power UP routine to reset TIPI latches.
-onreset				; 
+onreset				;
 	STWP	R5		; Hold WP for EQU based offsets.
 
 	CLR	@TDOUT		; Clear TIPI data output
 	CLR	@TCOUT		; Clear control output
 
-; trigger reset signal to RPi
+; If the PI is alive, trigger it to dirty RCIN
+	LI  R1,>F100   ; this is the brief reset echo for
+	                ; synchronizing the ack counter
+	MOVB R1,@TCOUT  ; send that to the PI.
+	LI	R2,>0400	; setup a limited loop
+!	MOVB @RCIN,R1   ; read the ack register from TIPI
+	CI	R1,>F100    ;
+	JEQ crureset    ; escape out of the limited retry loop
+	DEC R2
+	JNE -!			; if we leave hear early, RCIN will be 0xF1
+					; and later we get to check that full reset
+					; happened by RCIN becoming 0x00
+
+; Trigger reset signal to RPi
+; This kills the TipiService and restarts it asynchronously.
+crureset
 	SBO	1		; turn on the second cru bit
-	LI	R1,>0200
+	LI	R1,>0400
 !	DEC	R1
 	JNE	-!
-	
+
 ; turn off the reset signal so RPi service can finish starting
 	SBZ	1
 
 ; setup disk buffers if crubase is that of floppy controller
 	CI	R12,>1100
-	JNE	done
+	JNE	tipizero
 	LI	R2,>37D7	; room for 3 file buffers
 	MOV	R2,@VDPSTACK
 	LI	R1,VDPWA
@@ -40,7 +55,12 @@ fheadcopy
 	CI	R2,5
 	JNE	fheadcopy
 
+; Wait for TIPI to zero out RCIN when TipiService starts.
+tipizero
+	CLR	R1
+	MOVB	@RCIN, R1
+	JNE	tipizero
+
 ; Return to TI startup
-done
 	RT			; return to console