rp2040

commit 16068031ffd513bc9388c2059150bdc17c87ec23
parent 62de635eef84f10d862e88771739a678f9c8de71
Author: Matsuda Kenji <info@mtkn.jp>
Date:   Thu, 28 Mar 2024 09:48:08 +0900

update xpsr

Diffstat:
M
ex3/main.c
 | 
8
++++----
M
ex3/proc.s
 | 
16
+++++++++-------

2 files changed, 13 insertions(+), 11 deletions(-)
diff --git a/ex3/main.c b/ex3/main.c
@@ -54,15 +54,15 @@ main(void) {
 	p0.id = 0;
 	p0.r[13] = 0x20000100; // sp
 	p0.r[14] = (unsigned int) halt; // lr
-	p0.r[15] = (unsigned int) proc0 + 1; // pc
-	p0.r[16] = 0;
+	p0.r[15] = (unsigned int) proc0; // pc
+	p0.r[16] = 0x01000000; // EPSR's thumb bit
 	p0.next = &p1;
 
 	p1.id = 1;
 	p1.r[13] = 0x20000200; // sp
 	p1.r[14] = (unsigned int) halt; // lr
-	p1.r[15] = (unsigned int) proc1 + 1; // pc
-	p1.r[16] = 0;
+	p1.r[15] = (unsigned int) proc1; // pc
+	p1.r[16] = 0x01000000; // EPSR's thumb bit
 	p1.next = NULL;
 
 	set_psp();
diff --git a/ex3/proc.s b/ex3/proc.s
@@ -4,8 +4,12 @@
 proc0:
 	ldr r0, =msg0
 	bl puts
-	ldr r0, =0xdeadbeef
+	mov r0, #0
+	mov r1, #1
+	cmp r0, r1
+	sub sp, #4
 	wfi
+	add sp, #4
 	b proc0
 
 	.align 2
@@ -123,20 +127,18 @@ isr_alarm:
 	ldr r1, [r0, #(12 * 4)] // r12
 	str r1, [r2, #0x10]
 	ldr r1, [r0, #(13 * 4)] // psp
-	//msr psp, r1 // hard fault
+	msr psp, r1 // hard fault
 	ldr r1, [r0, #(14 * 4)] // lr
 	str r1, [r2, #0x14]
 	ldr r1, [r0, #(15 * 4)] // ReturnAddress
 	str r1, [r2, #0x18]
-//	ldr r1, [r0, #(16 * 4)] // xpsr
-//	str r1, [r2, #0x1c]
+	ldr r1, [r0, #(16 * 4)] // xpsr
+	str r1, [r2, #0x1c]
 
 	ldr r0, =(1000 * 1000)
 	bl set_alarm
 
-	pop {r5}
-
-	bx r5
+	pop {pc}
 
 	.align 2
 alarm_msg: