Load a development ARC file after JTAG programming (#99)

A /CORENAME.ARC will be loaded when loading via USB Blaster is
detected. CORENAME comes from the built-in config string.

fpga.c

@@ -940,6 +940,7 @@ void fpga_init(const char *name) {
   }
 
   user_io_detect_core_type();
+  user_io_init_core();
   mist_ini_parse();
   user_io_send_buttons(true);
   InitDB9();

main.c

@@ -197,10 +197,18 @@ int main(void)
     // tos config also contains cdc redirect settings used by minimig
     tos_config_load(-1);
 
-    char mod = 0;
+    char mod = -1;
 
-    if((USB_LOAD_VAR != USB_LOAD_VALUE) && !user_io_dip_switch1())
+    if((USB_LOAD_VAR != USB_LOAD_VALUE) && !user_io_dip_switch1()) {
         mod = arc_open("/CORE.ARC");
+    } else {
+        user_io_detect_core_type();
+        if(user_io_core_type() != CORE_TYPE_UNKNOWN && !user_io_create_config_name(s, "ARC", CONFIG_ROOT)) {
+            // when loaded from USB, try to load the development ARC file
+            iprintf("Load development ARC: %s\n", s);
+            mod = arc_open(s);
+        }
+    }
 
     if(mod < 0 || !strlen(arc_get_rbfname())) {
         fpga_init(NULL); // error opening default ARC, try with default RBF

user_io.c

@@ -304,7 +304,7 @@ void user_io_detect_core_type() {
 		archie_init();
 		break;
 
-	case CORE_TYPE_8BIT: {
+	case CORE_TYPE_8BIT:
 		puts("Identified 8BIT core");
 
 		// send core variant first to allow the FPGA choosing the config string
@@ -322,6 +322,16 @@ void user_io_detect_core_type() {
 
 		// get requested features
 		user_io_read_core_features();
+		break;
+
+	default:
+		iprintf("Unable to identify core (%x)!\n", core_type);
+		core_type = CORE_TYPE_UNKNOWN;
+	}
+}
+
+void user_io_init_core() {
+	if(core_type == CORE_TYPE_8BIT) {
 
 		// send a reset
 		user_io_8bit_set_status(UIO_STATUS_RESET, ~0);
@@ -416,15 +426,9 @@ void user_io_detect_core_type() {
 
 		// release reset
 		user_io_8bit_set_status(0, UIO_STATUS_RESET);
-
-	} break;
-	default:
-		iprintf("Unable to identify core (%x)!\n", core_type);
-		core_type = CORE_TYPE_UNKNOWN;
 	}
 }
 
-
 static unsigned short usb2amiga( unsigned  char k ) {
 	//  replace MENU key by RGUI to allow using Right Amiga on reduced keyboards
 	// (it also disables the use of Menu for OSD)

user_io.h

@@ -189,6 +189,7 @@ typedef struct {
 void user_io_reset();
 void user_io_init();
 void user_io_detect_core_type();
+void user_io_init_core();
 unsigned char user_io_core_type();
 uint32_t user_io_get_core_features();
 char minimig_v1();