struct srl_device
	local size
	label  .: size
	dev				rl 1
	rx_addr				rb 1
	tx_addr				rb 1
	type				rb 1
	subtype				rb 1
	rx_buf				ring_buf_ctrl
	tx_buf				ring_buf_ctrl
	error				rl 1
	; reserved area
	idvendor			rw 1
	idproduct			rw 1
	bcddevice			rw 1
	bcdusb				rw 1
	baudtype			rb 1
	size := $-.
end struct