Z86D86 Datasheet, PDF (46/80 Pages) Zilog, Inc. – 28-Pin Low-Voltage OTP Microcontroller

Z86D86
28-Pin Low-Voltage OTP Microcontroller
38
Table 18. CTR0 (D)00 Counter/Timer8 Control Register (Continued)
Field
Bit Position
Counter_INT_Mask ------1-
R/W
P34_Out
-------0
R/W
Note:
* Indicates the value upon Power-On Reset.
Value
0
1
0*
1
Description
Disable Time-Out Int.
Enable Time-Out Int.
P34 as Port Output
T8 Output on P34
T8 Enable
This field enables T8 when set (written) to 1.
Single/Modulo-N
When set to 0 (modulo-n), the counter reloads the initial value when the terminal
count is reached. When set to 1 (single pass), the counter stops when the terminal
count is reached.
Time-Out
This bit is set when T8 times out (terminal count reached). To reset this bit, a 1
must be written to this location.
Caution: Writing a 1 is the only way to reset the Terminal Count
status condition. Therefore, you must reset this bit before
using/enabling the counter/timers.
The first clock of T8 might not exhibit complete clock width
and can occur anytime when enabled.
Note: Care must be taken when utilizing the OR or AND commands
to manipulate CTR0, bit 5 and CTR1, bits 0 and 1
(demodulation mode). These instructions use a Read-Modify-
Write sequence in which the current status from the CTR0 and
CTR1 registers is ORed or ANDed with the designated value
and then written back into the registers.
For example, when the status of bit 5 is 1, a timer reset condition occurs.
T8 Clock
This bit defines the frequency of the input signal to T8.
PS008905-0105
PRELIMINARY