Z86D73
40/44/48-Pin Low-Voltage IR OTP
49
T16 Transmit Mode
In Normal or Ping-Pong Mode, the output of T16 when not enabled, is dependent
on CTR1, D0. If it is a 0, T16_OUT is a 1; if it is a 1, T16_OUT is 0. You can force
the output of T16 to either a 0 or 1 whether it is enabled or not by programming
CTR1 D3; D2 to a 10 or 11.
When T16 is enabled, TC16H * 256 + TC16L is loaded, and T16_OUT is switched
to its initial value (CTR1, D0). When T16 counts down to 0, T16_OUT is toggled
(in Normal or Ping-Pong Mode), an interrupt (CTR2, D1) is generated (if enabled),
and a status bit (CTR2, D5) is set. See Figure 26.
Z8 Data Bus
Positive Edge
Negative Edge
HI16
LO16
CTR2 D1
IRQ3
CTR2 D2
CTR2 D4, D3
Clock
Select
Clock
16-Bit
Counter T16
SCLK
T16_OUT
TC16H
Z8 Data Bus
TC16L
Figure 26. 16-Bit Counter/Timer Circuits
Note:
Global interrupts override this function as described in “Interrupts” on
If T16 is in Single-Pass Mode, it is stopped at this point (see Figure 27). If it is in
Modulo-N Mode, it is loaded with TC16H * 256 + TC16L, and the counting contin-
ues (see Figure 28).
You can modify the values in TC16H and TC16L at any time. The new values take
effect when they are loaded.
PS019402-1103
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