X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=simavr%2Fsim%2Favr_ioport.c;h=24a8a9bd5d6b43497e021304389edc652ad06676;hb=fb5a31d1e731a1d3f1993063496277c979ce356e;hp=3966996f0f865988beb15cc472bfda1b68d7ea91;hpb=6d2da708b0b554f5f70d0c74ce09d4dd279d49d2;p=simavr

diff --git a/simavr/sim/avr_ioport.c b/simavr/sim/avr_ioport.c
index 3966996..24a8a9b 100644
--- a/simavr/sim/avr_ioport.c
+++ b/simavr/sim/avr_ioport.c
@@ -38,19 +38,14 @@ static uint8_t avr_ioport_read(struct avr_t * avr, avr_io_addr_t addr, void * pa
 static void avr_ioport_write(struct avr_t * avr, avr_io_addr_t addr, uint8_t v, void * param)
 {
 	avr_ioport_t * p = (avr_ioport_t *)param;
-	uint8_t oldv = avr->data[addr];
 
 	avr_core_watch_write(avr, addr, v);
-	if (v != oldv) {
-		//	printf("PORT%c(%02x) = %02x (was %02x)\n", p->name, addr, v, oldv);
-		int mask = v ^ oldv;
-
-		// raise the internal IRQ callbacks
-		for (int i = 0; i < 8; i++)
-			if (mask & (1 << i))
-				avr_raise_irq(p->io.irq + i, (v >> i) & 1);
-		avr_raise_irq(p->io.irq + IOPORT_IRQ_PIN_ALL, v);
-	}
+	//	printf("PORT%c(%02x) = %02x (was %02x)\n", p->name, addr, v, oldv);
+
+	// raise the internal IRQ callbacks
+	for (int i = 0; i < 8; i++)
+		avr_raise_irq(p->io.irq + i, (v >> i) & 1);
+	avr_raise_irq(p->io.irq + IOPORT_IRQ_PIN_ALL, v);
 }
 
 /*
@@ -66,7 +61,8 @@ static void avr_ioport_pin_write(struct avr_t * avr, avr_io_addr_t addr, uint8_t
 
 /*
  * This is a the callback for the DDR register. There is nothing much to do here, apart
- * from triggering an IRQ in case any 'client' code is interested in the information.
+ * from triggering an IRQ in case any 'client' code is interested in the information,
+ * and restoring all PIN bits marked as output to PORT values.
  */
 static void avr_ioport_ddr_write(struct avr_t * avr, avr_io_addr_t addr, uint8_t v, void * param)
 {
@@ -74,6 +70,14 @@ static void avr_ioport_ddr_write(struct avr_t * avr, avr_io_addr_t addr, uint8_t
 
 	avr_raise_irq(p->io.irq + IOPORT_IRQ_DIRECTION_ALL, v);
 	avr_core_watch_write(avr, addr, v);
+
+	const uint8_t oldpin = avr->data[p->r_pin];
+	const uint8_t pin = (oldpin & ~v) | (avr->data[p->r_port] & v);
+	avr_core_watch_write(avr, p->r_pin, pin);
+	for (int i = 0; i < 8; i++)
+		if (((oldpin ^ pin) >> i) & 1)
+			avr_raise_irq(p->io.irq + i, (pin >> i) & 1);
+	avr_raise_irq(p->io.irq + IOPORT_IRQ_PIN_ALL, pin);
 }
 
 /*
@@ -192,6 +196,9 @@ void avr_ioport_init(avr_t * avr, avr_ioport_t * p)
 	// allocate this module's IRQ
 	avr_io_setirqs(&p->io, AVR_IOCTL_IOPORT_GETIRQ(p->name), IOPORT_IRQ_COUNT, NULL);
 
+	for (int i = 0; i < IOPORT_IRQ_COUNT; i++)
+		p->io.irq[i].flags |= IRQ_FLAG_FILTERED;
+
 	avr_register_io_write(avr, p->r_port, avr_ioport_write, p);
 	avr_register_io_read(avr, p->r_pin, avr_ioport_read, p);
 	avr_register_io_write(avr, p->r_pin, avr_ioport_pin_write, p);