tape training

boot.asm

@@ -113,6 +113,15 @@ init:
         di
         ld sp, #STACK_TOP
 
+        ; A reset may have interrupted a CTC service routine without executing
+        ; RETI.  Release any stale daisy-chain in-service latches before the
+        ; channels are reinitialized.  RETI acts as RET for each CALL while
+        ; also signalling end-of-interrupt to daisy-chained peripherals.
+        call release_daisy_chain
+        call release_daisy_chain
+        call release_daisy_chain
+        call release_daisy_chain
+
         call gsinit
 
         ; Setup interrupt mode 2
@@ -125,6 +134,9 @@ init:
 hang:
         jr hang
 
+release_daisy_chain:
+        reti
+
 .area _GSINIT
 gsinit:
         ld bc, #l__INITIALIZER