mirror of https://github.com/wwarthen/RomWBW.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
54 lines
1.7 KiB
54 lines
1.7 KiB
|
|
; -----------------------------------------------------------------------------
|
|
; Copyright 2021 Dimitri Theulings
|
|
;
|
|
; This file is part of Tasty Basic.
|
|
;
|
|
; Tasty Basic is free software: you can redistribute it and/or modify
|
|
; it under the terms of the GNU General Public License as published by
|
|
; the Free Software Foundation, either version 3 of the License, or
|
|
; (at your option) any later version.
|
|
;
|
|
; Tasty Basic is distributed in the hope that it will be useful,
|
|
; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
; GNU General Public License for more details.
|
|
;
|
|
; You should have received a copy of the GNU General Public License
|
|
; along with Tasty Basic. If not, see <https://www.gnu.org/licenses/>.
|
|
; -----------------------------------------------------------------------------
|
|
; Tasty Basic is derived from earlier works by Li-Chen Wang, Peter Rauskolb,
|
|
; and Doug Gabbard. Refer to the source code repository for details
|
|
; <https://github.com/dimitrit/tastybasic/>.
|
|
; -----------------------------------------------------------------------------
|
|
|
|
USRPTR_OFFSET .equ 09feh
|
|
INTERNAL_OFFSET .equ 0c00h
|
|
TEXTEND_OFFSET .equ 07dffh
|
|
STACK_OFFSET .equ 07fffh
|
|
|
|
tty_data .equ 7ch
|
|
tty_status .equ 7dh
|
|
rx_full .equ 1
|
|
tx_empty .equ 0
|
|
|
|
putchar:
|
|
call uart_tx_ready ; see if transmit is available
|
|
out (tty_data),a ; and send it
|
|
ret
|
|
uart_tx_ready:
|
|
push af
|
|
uart_tx_ready_loop:
|
|
in a,(tty_status)
|
|
bit tx_empty,a
|
|
jp z,uart_tx_ready_loop
|
|
pop af
|
|
ret
|
|
haschar:
|
|
in a,(tty_status) ; check if character available
|
|
bit rx_full,a
|
|
ret
|
|
|
|
getchar:
|
|
in a,(tty_data) ; get the character
|
|
ret
|
|
|