init of monolyzer project

[my-code/atmel.git] / monolyzer / uart.asm

diff --git a/monolyzer/uart.asm b/monolyzer/uart.asm
new file mode 100644 (file)
index 0000000..fbfbf3d
--- /dev/null
+++ b/monolyzer/uart.asm
@@ -0,0 +1,60 @@
+; uart functions
+
+; default uart settings / 19.2k @ 8 mhz
+; ifndef UART_BR_H
+.equ   UART_BR_H       = 0
+; ifndef UART_BR_L
+.equ   UART_BR_L       = 25
+
+UART_INIT:
+
+       ; baudrate
+       ldi tmp1,UART_BR_H
+       out UBRRH,tmp1
+       ldi tmp1,UART_BR_L
+       out UBRRL,tmp1
+
+       ; enable
+       ldi tmp1,(1<<RXEN)|(1<<TXEN)
+       out UCSRB,tmp1
+
+       ; frame format -> 8n1
+       ldi tmp1,(1<<UCSZ0)|(1<<UCSZ1)
+       out UCSRC,tmp1
+
+       ret
+
+UART_INT_RX_INIT:
+
+       in tmp1,UCSRB
+       sbr tmp1,(1<<RXCIE)
+       out UCSRB,tmp1
+
+       ret
+
+UART_INT_TX_INIT:
+
+       in tmp1,UCSRB
+       sbr tmp1,(1<<TXCIE)
+       out UCSRB,tmp1
+
+       ret
+
+UART_RX:
+
+       ; get/store received byte
+       sbis UCSRA,RXC
+               rjmp UART_RX
+       in uart_rxtx,UDR
+
+       ret
+
+UART_TX:
+
+       ; transmit content of uart_rxtx
+       sbis UCSRA,UDRE
+               rjmp UART_TX
+       out UDR,uart_rxtx
+
+       ret
+