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.syntax unified
.cpu cortex-m0plus
.thumb
.type main, %function
.global main, strbuf
main: LDR R5, =0x20002000
BL uart_recv // wait for keypress
loop: BL prompt // display address and data
LDR R0, inpbuf // get a line of input
BL getline
LDR R4, inpbuf // prepare input buffer
LDR R2, strbuf // prepare output buffer
MOVS R0, 0 // clear output buffer
STRB R0, [R2]
BL statement // call statement parser
BNE bad // print message if failure
MOVS R0, R1 // show assembled instruction
BL send_hex
LDR R0, =crlf
BL putstr
B loop // repeat
bad: PUSH {R0}
ADR R0, fail
BL putstr
POP {R0}
BL send_hex
LDR R0, =crlf
BL putstr
MOVS R0, R4
BL putstrln
B loop
prompt: PUSH {LR}
MOVS R0, R5
BL send_hex
MOVS R0, '
BL uart_send
LDR R0, [R5]
BL send_hex
MOVS R0, '
BL uart_send
POP {PC}
.align 4
inpbuf: .word 0x20001F00 // TODO getline buffer overflow
strbuf: .word 0x20001F80
.align 4
success: .asciz "The parser suceeded"
.align 4
fail: .asciz "The parser failed: "
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