Intel 8XC196MD Operation in Center-aligned and Edge-aligned Modes, Register Updates, Event Mode

8XC196MC, MD, MH USER’S MANUAL

Table 9-3. Operation in Center-aligned and Edge-aligned Modes

Step	Center-aligned Modes	Edge-aligned Modes
1	Load WG_COUNTER with WG_RELOAD.	Load WG_COUNTER with 0001H.
	Leave outputs deasserted.	Leave outputs deasserted.
2	When counter is enabled, begin counting down.	When counter is enabled, begin counting up.
	When WG_COUNTER reaches 1, wait 1 state,	Assert outputs when up count begins.
	then begin counting up. Assert outputs when up
	count begins.
3	When WG_COUNTER reaches the	When WG_COUNTER reaches the
	WG_COMPx value during the up count, deassert	WG_COMPx value, deassert the corresponding
	the corresponding phase’s outputs and continue	phase’s outputs and continue counting up.
	counting up.
4	When WG_COUNTER reaches the	When WG_COUNTER reaches the
	WG_RELOAD value, begin counting down.	WG_RELOAD value, update WG_RELOAD and
		go to step 1.

5When WG_COUNTER reaches the

WG_COMPx value during the down count, assert the corresponding phase’s outputs and continue counting down.

6When WG_COUNTER reaches 1, deassert outputs, update WG_RELOAD, and go to step 1.

The main differences between the center-aligned modes and among the edge-aligned modes are the events that control register updates. Table 9-4 lists the events that can cause register updates and the registers that are updated in each mode.

Table 9-4. Register Updates

	Center-aligned Modes		Edge-aligned Modes
Event	Mode 0	Mode 1	Mode 2		Mode 3	Mode 4
						(MH Only)
	Registers Updated			Registers Updated
	WG_RELOAD	WG_RELOAD	WG_RELOAD		WG_RELOAD	WG_RELOAD
WG_COUNTER	WG_COUNTER	WG_COUNTER	WG_COUNTER		WG_COUNTER	WG_COUNTER

=WG_RELOAD WG_COMPx WG_COMPx WG_COMPx WG_COMPx WG_COMPx

WG_OUTPUT† WG_OUTPUT† WG_OUTPUT† WG_OUTPUT† WG_OUTPUT†

WG_COUNTER = 1 —	WG_COMP x	—	—	—
WG_OUTPUT†	WG_OUTPUT†	WG_OUTPUT†	WG_RELOAD	WG_OUTPUT†
EPA event			WG_COUNTER
			WG_COMPx
			WG_OUTPUT†

†The WG_OUTPUT register is updated under these conditions if its synchronization bit is set; otherwise, changes take effect immediately.

9-8