X-Git-Url: http://cloudbase.mooo.com/gitweb/z180-stamp.git/blobdiff_plain/bad2d92d98f9990ee5ccf509c0eafe5b3af9f4dc..7f552300815ccadd45ebb3e7f0ae72a3b2e0c4e5:/avr/z80-if.c

diff --git a/avr/z80-if.c b/avr/z80-if.c
index d14d9d7..9492c28 100644
--- a/avr/z80-if.c
+++ b/avr/z80-if.c
@@ -54,7 +54,6 @@
  */
 
 #include <avr/io.h>
-#include <util/delay.h>
 #include <util/atomic.h>
 #include <stdio.h>
 #include "debug.h"
@@ -241,7 +240,7 @@ static void z80_busreq_hpulse(void)
 	z80_dbus_set_in();
 	z80_addrbus_set_tristate();
 
-	ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+	ATOMIC_BLOCK(ATOMIC_FORCEON) {
 		Z80_O_BUSREQ = 1;
 		Z80_O_BUSREQ = 1;	/* 2 AVR clock cycles */
 		Z80_O_BUSREQ = 0;	/* 2 AVR clock cycles */
@@ -497,20 +496,20 @@ static struct {
 	} fifo_dsc[NUM_FIFOS];
 
 
-void z80_memfifo_init(const fifo_t f, uint32_t adr)
+void z80_memfifo_init(const fifo_t f, uint32_t addr)
 {
+	fifo_dsc[f].base = addr;
 
-DBG_P(2, "z80_memfifo_init: %i, %lx\n", f, adr);
+	if (addr != 0) {
 
-	fifo_dsc[f].base = adr;
+DBG_P(2, "z80_memfifo_init: %i, %lx\n", f, addr);
 
-	z80_bus_cmd(Request);
-
-	fifo_dsc[f].mask = z80_read(adr + FIFO_BUFSIZE_MASK);
-	fifo_dsc[f].idx_in = z80_read(adr + FIFO_INDEX_IN);
-	fifo_dsc[f].idx_out = z80_read(adr + FIFO_INDEX_OUT);
-
-	z80_bus_cmd(Release);
+		z80_bus_cmd(Request);
+		fifo_dsc[f].mask = z80_read(addr + FIFO_BUFSIZE_MASK);
+		fifo_dsc[f].idx_in = z80_read(addr + FIFO_INDEX_IN);
+		fifo_dsc[f].idx_out = z80_read(addr + FIFO_INDEX_OUT);
+		z80_bus_cmd(Release);
+	}
 }
 
 
@@ -518,8 +517,7 @@ int z80_memfifo_is_empty(const fifo_t f)
 {
 	int rc = 1;
 
-	if (((Stat & S_MSG_PENDING) || f != fifo_in) && fifo_dsc[f].base != 0)
-	{
+	if (fifo_dsc[f].base != 0) {
 
 		uint32_t adr = fifo_dsc[f].base + FIFO_INDEX_IN;
 		uint8_t idx;
@@ -546,7 +544,8 @@ int z80_memfifo_is_full(const fifo_t f)
 	return rc;
 }
 
-uint8_t z80_memfifo_getc(const fifo_t f)
+
+uint8_t z80_memfifo_getc_wait(const fifo_t f)
 {
 	uint8_t rc, idx;
 
@@ -563,6 +562,24 @@ uint8_t z80_memfifo_getc(const fifo_t f)
 	return rc;
 }
 
+int z80_memfifo_getc(const fifo_t f)
+{
+	int rc = -1;
+
+	if (fifo_dsc[f].base != 0) {
+		uint8_t idx = fifo_dsc[f].idx_out;
+		z80_bus_cmd(Request);
+		if (idx != z80_read(fifo_dsc[f].base + FIFO_INDEX_IN)) {
+			rc = z80_read(fifo_dsc[f].base+idx);
+			fifo_dsc[f].idx_out = ++idx & fifo_dsc[f].mask;
+			z80_write(fifo_dsc[f].base+FIFO_INDEX_OUT, fifo_dsc[f].idx_out);
+		}
+		z80_bus_cmd(Release);
+	}
+
+	return rc;
+}
+
 
 void z80_memfifo_putc(fifo_t f, uint8_t val)
 {