ds_read_byte
rombuf[i] = ds_read_byte(&sc->sc_dsh);
usecs = (ds_read_byte(&sc->sc_dsh) * 1000000) / 256;
clkbuf = ds_read_byte(&sc->sc_dsh)
+ (ds_read_byte(&sc->sc_dsh)<<8)
+ (ds_read_byte(&sc->sc_dsh)<<16)
+ (ds_read_byte(&sc->sc_dsh)<<24);
static u_int8_t ds_read_byte(struct ds_handle *);