rp2040

commit e85f14c88403da72c4974ac32269c0961ae43ebd
parent cbccaeed3ea148f27be286115e930bdb67a9df45
Author: Matsuda Kenji <info@mtkn.jp>
Date:   Fri, 23 Feb 2024 09:17:46 +0900

move vtor to 0x10000000

Diffstat:
M
ex3/boot2.s
 | 
9
++++++---
M
ex3/main.s
 | 
12
++++++------
M
ex3/memmap.ld
 | 
2
+-

3 files changed, 13 insertions(+), 10 deletions(-)
diff --git a/ex3/boot2.s b/ex3/boot2.s
@@ -1,6 +1,11 @@
 .cpu cortex-m0plus
 .thumb
 
+	.section .vectors
+vectors: // this should be placed at 0x10000000
+	.word 0x20040000 // initial SP
+	.word (reset+1)  // entry point
+
 	.section .boot2
 setup_xip:
 	ldr r3, rom_base
@@ -11,7 +16,7 @@ setup_xip:
 	blx r2
 	blx r0
 
-	ldr r0, flash_main
+	ldr r0, =0x10000000
 	ldr r1, m0plus_vtor 
 	str r0, [r1, #0] // M0PLUS: VTOR
 	ldr r1, [r0, #4] // entry point
@@ -22,8 +27,6 @@ setup_xip:
 	.align 2
 rom_base:
 	.word 0x00000000
-flash_main:
-	.word 0x10000000 + 0x100
 m0plus_vtor:
 	.word 0xe0000000 + 0xed08
 literals:
diff --git a/ex3/main.s b/ex3/main.s
@@ -1,12 +1,8 @@
 .cpu cortex-m0plus
 .thumb
 
-	.section .vectors
-vectors:
-	.word 0x20040000 // initial SP
-	.word (reset+1)  // entry point
-
 	.section .text
+	.global reset
 reset:
 	// unreset gpio, pll_sys, uart0
 	ldr r0, =(1 << 22 | 1 << 12 | 1 << 5) // uart0 | pll_sys | io_bank0
@@ -90,7 +86,11 @@ wait_vco:
 
 	// set systick timer
 	ldr r3, ppb_base
-	ldr r0, =0xffffff
+	// clear count
+	ldr r1, =0xe018
+	str r0, [r3, r1] // M0PLUS: SYST_CVR
+	// set reset value
+	ldr r0, =0xf423f // 1 sec
 	ldr r1, =0xe014
 	str r0, [r3, r1] // M0PLUS: SYST_RVR
 	// enable systick timer
diff --git a/ex3/memmap.ld b/ex3/memmap.ld
@@ -7,12 +7,12 @@ MEMORY
 SECTIONS
 {
 	.boot2 : {
+		*(.vectors)
 		*(.boot2)
 		. = 0x100;
 	} > FLASH
 
 	.text : {
-		*(.vectors)
 		*(.text)
 	} > FLASH
 }