.syntax unified .cpu cortex-m0plus .thumb .type main, %function .global main, strbuf main: LDR R5, =0x20002000 BL uart_recv loop: BL prompt LDR R0, inpbuf BL getline LDR R0, inpbuf BL putstrln LDR R4, inpbuf LDR R2, strbuf MOVS R0, 0 STRB R0, [R2] BL statement BNE bad good: ADR R0, success PUSH {R1} BL putstrln MOVS R0, R4 BL putstrln POP {R0} BL send_hex LDR R0, =crlf BL putstr B loop bad: ADR R0, fail BL putstrln MOVS R0, R4 BL putstrln B loop never: BL uart_recv LDR R0, =0x20000001 BX R0 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"