/*#include "romhdr.S"*/
#include "hw.S"

/*
ch2&3: TxD1,RxD1
*/

/* allegedly there's a subroutine at 0xEFFA1 that sends a single byte over the TOOL0 line */

.global _start
_start:

	call !hw_init
	call !port_init
	call !port_toggle

1:	br $1b

hw_init:
	di
	; systeminit
	; PIOR = 0

	; ADPC = 1
	; PMC bit = 0

	; PM1 = 6(?)
	; CMC = 0
	; MSTOP,XTSTOP bits = 1,1
	; MCM0 bit = 0 ; hi-speed OCO clock as main clock
	; CSS bit = 0 ; main system clock = periph clock

	; PER0 SAU1EN bit (3) = 1
	; SPS0 = 0x44 ; or *12?  ; CK00,CK01 @ 2MHz

	; ST0 = 0xf ; stop all channels
	; STMK0,STIF0 bits = 1,0 ; disable interrupts
	; SRMK0,SRIF0 bits = 1,0 ; disable interrupts
	; SREK0,SREF0 bits = 1,0 ; disable interrupts
	; SMR00 = 0x22          ; ch0clock = CK00, start trig=sw falling edge, UART mode, xferend irq en
	; SCR00 = 0x8297        ; tx only, clock type 1, error irq en, even parity, lsbfirst, 8bit data, 1bit stop
	; SDR00 = 0xce00        ; opclk/208
	; NFEN0 = 0x0001        ; RxD noise filter enable
	; SIR01 = 0x0007        ; clear error
	; SMR01 = 0x0122        ; ch1clock = CK00; start trig=RxD falling edge, UART mode, xferend irq en
	; SCR01 = 0x4697        ; rx only, clock type 1, error irq en, even parity, lsbfirst, 8bit data, 1bit stop
	; SDR01 = 0xce00        ; opclk/208 ; use opclk/17 (0x0f00) instead for 115.2kbaud?
	; SO00,SOE00 bits = 1,1 ; prepare using ch0
	; PM1 PM11 bit = 1          ; RxD pin as input
	; P1,PM1 P12,PM12 bits = 1,0   ; TxD as output

	; SO00 bit = 1 ; TxD output level
	; SOE00 bit = 1 ; enable UART
	; SS00,SS01 bits = 1,1 ; enable UART

	; TXD0 = data ; xmit

	;ei ; nah
	ret

port_init:
	; P33 as output using GPIO
	; PM3 bit 3 = 0
	; PU3 bit 3 = 0 (no pullup)
	; PMC3 bit 3 = 0 (digital IO)
	; PIOR0 bit 6 = 0
	; POM3 bit 3 = 0
	; toggle P3 bit 3
	clr1 !PM3.3
	clr1 !PU3.3
	clr1 !PIOR0.6
	clr1 !POM3.3
	ret

port_toggle:
	set1 !P3.3
	nop
	nop
	clr1 !P3.3
	br $port_toggle

uart_init:
	;; PMC00=0 PM00=1 ; RxD1 en
	; PIO2.3 = 1
	; PMC20=0 PM20=0 P20=1 ; TxD1 en
	ret

uart_send_byte:
	; todo
	; TODO: wait for sent?
	ret