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style: prettier math (thx asm6809), add MIT license to boot.s, remove stray (

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Amber
2024-11-22 10:17:26 -05:00
parent 3e4e0487a3
commit 4a50a80e1f
1 changed files with 13 additions and 12 deletions
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code/boot/src/boot.s
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@@ -1,23 +1,24 @@
; CHIBI PC-09 Prototype #1 Boot ROM
; (Copyright (c) 2024 Amber Zeller
; Copyright (c) 2024 Amber Zeller
; Licensed under MIT
; UART registers
UART EQU $7F00
; When DLAB = 0:
BUFR EQU UART ; TX/RX Buffer (Read for RX, Write for TX)
IER EQU UART+1 ; Interrupt Enable Register
IIR EQU UART+1 ; Interrupt Enable Register (Upon Read)
BUFR EQU UART ; TX/RX Buffer (Read for RX, Write for TX)
IER EQU UART + 1 ; Interrupt Enable Register
IIR EQU UART + 1 ; Interrupt Ident Register (Upon Read)
; When DLAB = 1
DLL EQU UART ; Divisor Latch (LSB)
DLM EQU UART+1 ; Divisor Latch (MSB)
DLL EQU UART ; Divisor Latch (LSB)
DLM EQU UART + 1 ; Divisor Latch (MSB)
FCR EQU UART+2 ; FIFO Control Register (Upon Write)
LCR EQU UART+3 ; Line Control Register
MCR EQU UART+4 ; MODEM Control Register
LSR EQU UART+5 ; Line Status Register
MSR EQU UART+6 ; MODEM Status Register
SCR EQU UART+7 ; Scratch Register (Not for control just spare RAM)
FCR EQU UART + 2 ; FIFO Control Register (Upon Write)
LCR EQU UART + 3 ; Line Control Register
MCR EQU UART + 4 ; MODEM Control Register
LSR EQU UART + 5 ; Line Status Register
MSR EQU UART + 6 ; MODEM Status Register
SCR EQU UART + 7 ; Scratch Register (Not for control just spare RAM)
ORG $8000