# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1489355021 -7200
# Node ID ff8af8351282a4010fbc96a579f6f49d1cc1db0c
# Parent  abb348704dece74421bcc3c58d7afbb37b3f487f
works

diff -r abb348704dec -r ff8af8351282 Makefile
--- a/Makefile	Sun Mar 12 04:27:43 2017 +0200
+++ b/Makefile	Sun Mar 12 23:43:41 2017 +0200
@@ -27,7 +27,7 @@
 
 .PHONY: fuses
 fuses:
-	avrdude -c usbtiny -p $(mcu_dude) -U lfuse:w:0xf7:m -U hfuse:w:0x99:m -U efuse:w:0xff:m
+	avrdude -c usbtiny -p $(mcu_dude) -U lfuse:w:0xf7:m -U hfuse:w:0xd9:m -U efuse:w:0xff:m
 
 .PHONY: program
 program: $(hex)
diff -r abb348704dec -r ff8af8351282 main.c
--- a/main.c	Sun Mar 12 04:27:43 2017 +0200
+++ b/main.c	Sun Mar 12 23:43:41 2017 +0200
@@ -64,7 +64,7 @@
 
 int main(void)
 {
-	init_serial(38400);
+	init_serial(115200);
 	run_mode();
 
 	sei();
@@ -101,12 +101,12 @@
 
 	case 'p':
 		prog_mode();
-		printf("OK programming mode\n");
+		puts("OK programming mode");
 		break;
 
 	case 'b':
 		run_mode();
-		printf("OK boot mode\n");
+		puts("OK run mode");
 		break;
 
 	case 'a':
@@ -116,26 +116,26 @@
 
 	case 'w':
 		if(running) {
-			printf("ERR running\n");
+			puts("ERR running");
 			break;
 		}
 		if(addr >= MEM_SIZE) {
-			printf("ERR overflow\n");
+			puts("ERR overflow");
 			break;
 		}
 
 		data = strtol(input + 1, &endp, 0);
 		sram_write(addr++, data);
-		printf("OK %d\n", (int)data);
+		puts("OK");
 		break;
 
 	case 'r':
 		if(running) {
-			printf("ERR running\n");
+			puts("ERR running");
 			break;
 		}
 		if(addr >= MEM_SIZE) {
-			printf("ERR overflow\n");
+			puts("ERR overflow");
 			break;
 		}
 
@@ -144,7 +144,7 @@
 		break;
 
 	default:
-		printf("ERR unknown command\n");
+		puts("ERR unknown command");
 		break;
 	}
 }
@@ -152,14 +152,15 @@
 void run_mode(void)
 {
 	/* tri-state everything and release the reset line */
+	/* do not tri-state WE and keep it high */
 	DDRA = 0;
 	PORTA = 0;
 	DDRB = 0;
 	PORTB = 0;
 	DDRC = 0;
 	PORTC = 0;
-	DDRD = RST_BIT;
-	PORTD = RST_BIT;
+	DDRD = RST_BIT | WE_BIT;
+	PORTD = RST_BIT | WE_BIT;
 
 	running = 1;
 }
@@ -167,7 +168,7 @@
 void prog_mode(void)
 {
 	/* hold the reset line and take control of the bus */
-	PORTD = 0;
+	PORTD = WE_BIT;	/* keep WE high to avoid writing random bytes */
 	DDRD = 0xff;
 	DDRA = 0xff;
 	DDRB = 0xff;
@@ -192,7 +193,6 @@
 
 	/* pulse WE */
 	PORTD &= ~WE_BIT;
-	_delay_us(0.1);
 	/* WE should be low for at least 9ns, which is way faster than we can toggle it anyway */
 	PORTD |= WE_BIT;
 }