Rainbow Electronics ATA5812 - Manual (Page 41)

41
ATA5811/ATA5812 [Preliminary]
4689B–RKE–04/04
If the transceiver is in any active mode (Idle, AUX, TX, RX, RX_Polling), an integrated
debounce logic is active. If there is an event on pin Tn a debounce counter is set to 0
(T = 0) and started. The status is updated, an interrupt is issued and the debounce
counter is stopped after reaching the counter value T = 8195
×
T
DCLK
.
An event on the same key input before reaching T = 8195 × T
DCLK
stops the debounce
counter. An event on an other key input before reaching T = 8195
×
T
DCLK
resets and
restarts the debounce counter.
While the debounce counter is running, the bits VSOUT_EN and CLK_ON in control
register 3 are set to 1.
The interrupt is deleted after reading the status register or executes the command
Delete_IRQ.
If a pin Tn is not used, it can be left open because of an internal pull-up resistor (typically
50 k
Ω
).
Figure 29. Timing Flow Pin Tn, Status Bit STn
Event on Pin Tn ?
N
Y
Event on Pin
Tn ? N
Y
T = 8195
×
T
? N
Y
T = 0
Start debounce counter
Stop debounce counter
STn = 1;
IRQ = 1
Pin Tn = 0 ?
Stop debounce counter
STn = 0;
IRQ = 1
Y
N
IDLE Mode or
AUX Mode or
TX Mode or
RX Polling Mode or
RX Mode
Tn = STn ?
Y
N
Stop debounce counter