akkera 102
SPC music playback tools for real snes apu
Diff: apu.cpp
- Revision:
- 2:62e6e22f8be2
- Parent:
- 1:02a06cd10a33
diff -r 02a06cd10a33 -r 62e6e22f8be2 apu.cpp
--- a/apu.cpp Mon Jan 09 13:58:58 2017 +0000
+++ b/apu.cpp Wed Jan 11 16:00:29 2017 +0000
@@ -1,206 +1,210 @@
-/* hwapu - SPC music playback tools for real snes apu
- * Copyright (C) 2004-2005 Raphael Assenat <raph@raphnet.net>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-#include <stdio.h>
-#include <string.h>/**/
#include "apu.h"
-#include <time.h>
-// #include <sys/time.h>
#include "mbed.h"
-
+#include "gpio.h"
-//#define TRACE_RW
+// cmd.cpp
+extern int g_verbose;
-extern int g_verbose; // from main.c
+static int port0 = 0;
-/******************** G L O B A L S ************************************/
-static int port0=0;
-static APU_ops *apu_ops = NULL;
-
-void apu_setOps(APU_ops *ops)
+void apu_init(void)
{
- apu_ops = ops;
+ port0 = 0;
+ gpio_init();
}
-static int SetPort0 (short data)
+// Reset the APU by whatever means it needs reset.
+void apu_reset(void)
{
- port0=data;
- return 0;
+ gpio_reset();
}
-void apu_write (int address, unsigned char data)
+unsigned char apu_read(int address)
{
-//#ifdef TRACE_RW
-// printf("apu_write: a=%d, %02x\n", address, data);
-//#endif
- apu_ops->write(address, data);
-}
+ unsigned char tmp = gpio_read(address);
-unsigned char apu_read (int address)
-{
- unsigned char tmp = apu_ops->read(address);
-//#ifdef TRACE_RW
// printf("apu_read: a=%d -> %02x\n", address, tmp);
-//#endif
return tmp;
}
-/* Write to address 'address', write the previously
- * read value from port0 back to port 0 and wait
- * for port0 value to be different from the written one.
- */
-int apu_writeHandshake(int address, int data)
+void apu_write(int address, unsigned char data)
{
-// int i;
-// i = 0;
- apu_write(address, data);
- apu_write(0,port0);
-
- if (!apu_waitInport(0, port0, 500)) {
- return 1;
- }
- port0++;
- if (port0 == 256)
- port0 = 0;
+// printf("apu_write: a=%d, %02x\n", address, data);
- return 0;
-
-
+ gpio_write(address, data);
}
-
+// Write many bytes using handshake (see apu_writeHandshake)
int apu_writeBytes(unsigned char *data, int len)
{
- int i;
-#ifdef TRACE_RW
- printf("apu_writeBytes: %d...\n", len);
-#endif
- for (i=0; i<len; i++) {
- if (apu_writeHandshake(1, data[i])) { return 1; }
+// printf("apu_writeBytes: %d...\n", len);
+
+ for(int i=0; i<len; i++)
+ {
+ if(apu_writeHandshake(1, data[i]))
+ {
+ return 1;
+ }
}
+
return 0;
}
-void apu_reset(void) //Reset the APU by whatever means it needs reset.
+// Write to address 'address', write the previously
+// read value from port0 back to port 0 and wait
+// for port0 value to be different from the written one.
+int apu_writeHandshake(int address, int data)
{
- apu_ops->reset();
+ apu_write(address, data);
+ apu_write(0, port0);
+
+ if(!apu_waitInport(0, port0, 500))
+ {
+ return 1;
+ }
+ if(++port0 == 256)
+ {
+ port0 = 0;
+ }
+
+ return 0;
}
-/* return false on timeout, otherwise true */
+// return false on timeout, otherwise true
int apu_waitInport(int port, unsigned char data, int timeout_ms)
{
- // struct timeval tv_before, tv_now;
- // gettimeofday(&tv_before, NULL);
- int elaps_milli;
+// printf("apu_waitInport: addr: %d, data: %02x\n", port, data);
+
+ int ms;
Timer t;
t.start();
-#ifdef TRACE_RW
- printf("apu_waitInport: addr: %d, data: %02x\n",port,data);
-#endif
-
- while(apu_read(port)!=data) {
- //usleep(1);
-// gettimeofday(&tv_now, NULL);
-// elaps_milli = (tv_now.tv_sec - tv_before.tv_sec) * 1000;
-// elaps_milli += (tv_now.tv_usec-tv_before.tv_usec)/1000;
- elaps_milli = t.read_ms();
- if (elaps_milli > timeout_ms )
+ while(apu_read(port) != data)
+ {
+ ms = t.read_ms();
+ if(ms > timeout_ms)
{
- if (g_verbose)
- printf("timeout after %d milli\n", elaps_milli);
+ if(g_verbose)
+ {
+ printf("timeout after %d milli\n", ms);
+ }
+
return 0;
}
}
+
return 1;
}
+// Initialise an spc transfer at 'address'.
+// To be used after reset of after jumping to rom
+//
+// Use apu_newTransfer for additional transfers
+//
+// return -1 on error, 0 if success
int apu_initTransfer(unsigned short address)
{
- /* Initializing the transfer */
- /* Wait for port 2140 to be $aa */
- if (!apu_waitInport(0, 0xaa, 500)) {
- if (g_verbose)
+ // Initializing the transfer
+ // Wait for port 2140 to be $aa
+ if(!apu_waitInport(0, 0xaa, 500))
+ {
+ if(g_verbose)
+ {
printf("Should read 0xaa, but reads %02x\n", apu_read(0));
- return -1;
- }
- /* and Wait for port 2141 to be $bb */
- if (!apu_waitInport(1, 0xbb, 500)) {
- if (g_verbose)
- printf("Should read 0xaa, but reads %02x\n", apu_read(0));
+ }
+
return -1;
}
- /* The spc is now ready */
- /* Write any value other than 0 to 2141 */
- apu_write(1, 1);
- /* Write the destination address to poirt $2142 and $2143, with the
- * low byte written at $2142 */
- apu_write(2, address&0xff); // low
- apu_write(3, (address&0xff00)>>8); // high So our code will go at $0002
- /* Write $CC to port $2140 */
- apu_write(0, 0xCC);
+ // and Wait for port 2141 to be $bb
+ if(!apu_waitInport(1, 0xbb, 500))
+ {
+ if(g_verbose)
+ {
+ printf("Should read 0xaa, but reads %02x\n", apu_read(0));
+ }
- /* Wait for $2140 to be $CC */
- if (!apu_waitInport(0, 0xcc, 500)) {
- if (g_verbose)
- printf("Should read 0xcc, but reads %02x\n", apu_read(0));
return -1;
}
- SetPort0(0);
-
+ // The spc is now ready
+
+ // Write any value other than 0 to 2141
+ apu_write(1, 1);
+
+ // Write the destination address to poirt $2142 and $2143, with the
+ // low byte written at $2142
+ apu_write(2, (address & 0x00ff)); // low
+ apu_write(3, (address & 0xff00) >> 8); // high So our code will go at $0002
+
+ // Write $CC to port $2140
+ apu_write(0, 0xCC);
+
+ // Wait for $2140 to be $CC
+ if(!apu_waitInport(0, 0xcc, 500))
+ {
+ if(g_verbose)
+ {
+ printf("Should read 0xcc, but reads %02x\n", apu_read(0));
+ }
+
+ return -1;
+ }
+
+ port0 = 0;
return 0;
}
+// initialise a new transfer after the first transfer.
+//
+// returns 0 on success, -1 on error
int apu_newTransfer(unsigned short address)
{
int i;
- apu_write(1,1);
- apu_write(3, (address&0xff00)>>8);
- apu_write(2, (address & 0xff));
+ apu_write(1, 1);
+ apu_write(3, (address & 0xff00) >> 8);
+ apu_write(2, (address & 0x00ff));
+
+ i = apu_read(0);
+ i += 2;
+ i &= 0xff;
- i = apu_read(0);
- i += 2; i &= 0xff;
- if (!i) { i += 2; } // if it's 0, increase it again
+ // if it's 0, increase it again
+ if(!i)
+ {
+ i += 2;
+ }
apu_write(0, i);
- if (!apu_waitInport(0, i, 500)) {
- fprintf(stderr, "apu_newTransfer: timeout\n"); return -1;
+
+ if(!apu_waitInport(0, i, 500))
+ {
+ fprintf(stderr, "apu_newTransfer: timeout\n");
+ return -1;
}
- SetPort0(0);
-
+ port0 = 0;
return 0;
}
+// End transfer and jump to address
void apu_endTransfer(unsigned short start_address)
{
int i;
apu_write(1, 0);
- apu_write(3, (start_address & 0xff00)>>8);
- apu_write(2, (start_address & 0xff));
+ apu_write(3, (start_address & 0xff00) >> 8);
+ apu_write(2, (start_address & 0x00ff));
- i = apu_read(0);
- i +=2; i &= 0xff;
- if (!i) { i+=2 ; } // if it's 0, increase it again
+ i = apu_read(0);
+ i += 2;
+ i &= 0xff;
+
+ // if it's 0, increase it again
+ if(!i)
+ {
+ i+=2;
+ }
apu_write(0, i);
}
-
-