HSSRR
if (sci_getreg(port, HSSRR)->size) {
sci_serial_out(port, HSSRR, hssrr);
if (sci_getreg(port, HSSRR)->size)
regs->hssrr = sci_serial_in(port, HSSRR);
if (sci_getreg(port, HSSRR)->size)
sci_serial_out(port, HSSRR, regs->hssrr);
[HSSRR] = { 0x40, 16 },