RCBR
up->curregs[R11] = TCBR | RCBR;
up->curregs[R11] = TCBR | RCBR;
write_zsreg(uap, 11, RCBR | TCBR);
uap->curregs[R11] = TCBR | RCBR;
up->curregs[R11] = TCBR | RCBR;
up->curregs[R11] = TCBR | RCBR;
TCBR | RCBR, /* write 11 */