Z86L972 Datasheet, PDF (74/91 Pages) Zilog, Inc. – Low-Voltage Microcontrollers

Z86L972/Z86L973/Z86L974
Low-Voltage Microcontrollers
67
T8/T16 Control Register A (CTR1)
The T8/T16 Control Register A controls the functions in common with both the T₈
and T₁₆ counter/timers. The T₈ and T₁₆ counter/timers have two primary modes of
operation: Transmit Mode and Demodulation Mode. Transmit Mode is used for
generating complex waveforms. The Transmit Mode has two submodes: Normal
Mode and Ping-Pong Mode. The settings for CTR1 in Transmit Mode are given in
Table 35.
Table 35. CTR1 Register (In Transmit Mode) (Group/Bank 0Dh, Register 1)
Bit
7
6
5
4
Bit/Field
P43
Mode Out
T8/T16_Logic
R/W
R/W R/W R/W R/W
Reset
0
0
0
0
R = Read, W = Write, X = Indeterminate
Bit
Position
Bit/Field
R/W Value
7_______ Mode
R/W 1
0
_6______ P43_Out
R/W 1
0
__54____ T₈/T₁₆ Logic
R/W 11
10
01
00
____32__ Transmit_
Submode
R/W 11
10
01
00
______1_ Initial_T8_Out R/W 1
0
_______0 Initial_T16_Out R/W 1
0
3
2
Transmit_
Submode
R/W R/W
0
0
1
0
Initial_
Initial_ T16_
T8_Out Out
R/W R/W
0
0
Description
Demodulation
Transmit
P43 configured as T8/T16 Output
P43 configured as I/O
NAND
NOR
OR
AND
T16_Out = 1
T16_Out = 0
Ping-Pong Mode
Normal Operation
T8_Out set to 1 initially
T8_Out set to 0 initially
T16_Out set to 1 initially
T16_Out set to 0 initially
PS010504-1002
PRELIMINARY