z86d73 ZiLOG Semiconductor, z86d73 Datasheet - Page 55

• Manufacturer Part Number: z86d73
• Description: 40/44/48-pin Low-voltage
• Manufacturer: ZiLOG Semiconductor

PS019402-1103
Positive Edge
Negative Edge
CTR2 D4, D3
SCLK
Z8 Data Bus
Z8 Data Bus
Select
Clock
Note:
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.
Figure 26. 16-Bit Counter/Timer Circuits
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.
Global interrupts override this function as described in “Interrupts” on
page 53.
TC16H
HI16
Clock
P
Counter T16
16-Bit
R
E
L
I
M
TC16L
LO16
I
N
A
40/44/48-Pin Low-Voltage IR OTP
R
CTR2 D2
Y
CTR2 D1
T16_OUT
Z86D73
IRQ3
49