feat: modularized with lwtools build system

2025-08-31 14:42:14 -05:00
parent c67176e99a
commit 677b3cb02d
9 changed files with 164 additions and 120 deletions
--- a/code/boot/src/reset.s
+++ b/code/boot/src/reset.s
@@ -0,0 +1,35 @@
+; CHIBI PC-09 Prototype #1 Boot ROM -- Reset Handler
+; Copyright (c) 2024-2025 Amber Zeller, Gale Faraday
+; Licensed under MIT
+
+  INCLUDE "hardware.inc"
+  INCLUDE "serial.inc"
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;
+;; Hardware Initialization Routines
+;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+  SECTION RESET
+
+  EXPORT RESET
+
+RESET
+  ; 8n1 Serial Enable DLAB
+  lda #UARTF_LCR_WLS | UARTF_LCR_DLAB
+  sta UART_LCR
+  ; REVIEW: Potential endianness hiccough here
+  ldd #$0C00           ; Set divisor to 12 (9600 baud)
+  sta UART_DLM
+  stb UART_DLL
+  lda #(UARTF_LCR_WLS) ; 8n1 serial, disable DLAB
+  sta UART_LCR
+  lda #(UARTF_MCR_RTS) ; Enable Request-to-Send
+  sta UART_MCR
+  lda #'H               ; send 'H'
+  sta UART_BUFR
+WAIT@
+  sync                 ; Wait for interrupts
+  nop
+  bra WAIT@