23 lines
337 B
ArmAsm
23 lines
337 B
ArmAsm
.code
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UART_TX = $efe6
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UART_RX = UART_TX
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UART_STATUS = $efe7
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UART_CONTROL = UART_STATUS
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main:
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ldx #$00
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loop:
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lda UART_STATUS ; see if bit 0 is set
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bit #$01
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beq loop
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lda UART_RX ; read rx buffer if so
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sta UART_TX ; transmit it back again
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bra loop
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.segment "VECTORS"
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.addr main
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.addr main
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.addr main
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