CLKEVT
val = readw(gpt_base + CR(CLKEVT));
writew(val, gpt_base + CR(CLKEVT));
writew(period, gpt_base + LOAD(CLKEVT));
val = readw(gpt_base + CR(CLKEVT));
writew(val, gpt_base + CR(CLKEVT));
u16 val = readw(gpt_base + CR(CLKEVT));
writew(val & ~CTRL_ENABLE, gpt_base + CR(CLKEVT));
writew(cycles, gpt_base + LOAD(CLKEVT));
writew(val, gpt_base + CR(CLKEVT));
writew(INT_STATUS, gpt_base + IR(CLKEVT));
writew(CTRL_PRESCALER16, gpt_base + CR(CLKEVT));
u16 val = readw(gpt_base + CR(CLKEVT));
writew(val, gpt_base + CR(CLKEVT));