rp2040

commit ce2125ad05e2d3ff10e5cc8bfd7db7739a888004
parent 758fcb6332fb119f5f036459bb5c4179ad85d157
Author: Matsuda Kenji <info@mtkn.jp>
Date:   Wed, 22 Mar 2023 09:24:47 +0900

add uart read/write. something wrong

Diffstat:
M
main.s
 | 
27
++++++++++++++++++++++++++-

1 file changed, 26 insertions(+), 1 deletion(-)
diff --git a/main.s b/main.s
@@ -115,7 +115,8 @@ pll_lock:
 	str r1, [r0, #0x2c] // UART0_UARTLCR_H
 
 loop:
-	bl p0
+	bl uart0_read
+	bl uart0_write
 	b loop
 
 // functions
@@ -141,6 +142,30 @@ reset_chk:
 	beq reset_chk
 	bx lr
 
+uart0_write:
+	mov r1, #0xFF
+	and r0, r0, r1
+	ldr r1, uart0_base
+	mov r2, #32
+uart0_txff:
+	ldr r3, [r1, #0x18] // UART0_UARTFR
+	and r3, r3, r2
+	bne uart0_txff
+	str r0, [r1, #0] // UART0_UARTDR
+	bx lr
+
+uart0_read:
+	ldr r1, uart0_base
+	mov r2, #16
+uart0_rxfe:
+	ldr r3, [r1, #0x18] // UART0_UARTFR
+	and r3, r3, r2
+	bne uart0_rxfe
+	ldr r0, [r1, #0] // UART0_UARTDR
+	mov r1, #0xFF
+	and r0, r0, r1
+	bx lr
+
 pr:
 	// print register
 	push {lr}