z86l88 ZiLOG Semiconductor, z86l88 Datasheet - Page 57

• Manufacturer Part Number: z86l88
• Description: Low-voltage Ir Microcontroller
• Manufacturer: ZiLOG Semiconductor

PS024102-0804
Note:
CTR2 D4, D3
Sixteen-Bit Counter/Timer Circuits
Figure 38 shows the 16-bit counter/timer circuits.
SCLK
Z8 Data Bus
Figure 38. 16-Bit Counter/Timer Circuits
T16 Transmit Mode
In Normal or Ping-Pong Mode, the output of T16, when not enabled, is dependent
on CTR1, D0. If the result 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 pro-
gramming 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 is generated if enabled (CTR2 D1), and
a status bit (CTR2 D5) is set.
If T16 is in Single-Pass Mode, T16 is stopped at this point (see Figure 39). If T16
is in Modulo-N Mode, T16 is loaded with TC16H * 256 + TC16L and the counting
continues (see Figure 40).
Z8 Data Bus
Neg Edge
Pos Edge
Global interrupts override this function as described in
“Interrupts” on page 54.
Select
Clock
TC16H
Clock
HI16
Counter
16-Bit
T16
LO16
TC16L
Low-Voltage IR Microcontroller
CTR2 D2
CTR2 D1
T16_OUT
Z86L88
IRQ3
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