Z86L972 Datasheet, PDF (71/91 Pages) Zilog, Inc. – Low-Voltage Microcontrollers

Z86L972/Z86L973/Z86L974
Low-Voltage Microcontrollers
64
Port 6 Control and Mode Registers (P6 and P6M)
Port 6 is a general-purpose 8-bit, bidirectional I/O port, as shown in Table 30.
Each of the eight Port 6 I/O lines can be independently programmed as either
input or output using the Port 6 Mode Register (see Table 31.)
Table 30. P6 Register [Group/Bank 00h, Register 6 (R6)]
Bit
7
6
5
4
Bit/Field Port 6 Data
R/W
R/W R/W R/W R/W
Reset
X
X
X
X
R = Read, W = Write, X = Indeterminate
Bit
Position
Bit/Field
R/W Value
76543210 Port 6 Data
R/W Data
3
2
1
0
R/W R/W R/W R/W
X
X
X
X
Description
Port 6 Input/Output Register
Table 31. P6M Register (Group/Bank 0Fh, Register 6)
Bit
7
6
5
4
Bit/Field P67M P66M P65M P64M
R/W
R/W R/W R/W R/W
Reset
1
1
1
1
R = Read, W = Write, X = Indeterminate
Bit
Position
Bit/Field
R/W Value
76543210 Port 6 Mode
(by bit)
Select
R/W 1
0
3
P63M
R/W
1
2
P62M
R/W
1
Description
Input
Output
1
P61M
R/W
1
0
P60M
R/W
1
A bit set to 1 in the P6M Register configures the corresponding bit in Port 6 as an
input, while a bit set to 0 configures an output line.
Timer Control Registers—General-Purpose Timer (T1)
The Z86L972/Z86L973/Z86L974 family provides one standard 8-bit Z8 counter/
timer, T1, driven by its own 6-bit prescaler, PRE1. T1 is independent of the pro-
cessor instruction sequence, relieving software from time-critical operations such
as interval timing or event counting. There are three registers that control the
operation of T1: T1 Data Register (T1), T1 Mode Register (TMR), and T1 Prescale
Register (PRE1). Because the timer, prescaler, and mode register are mapped
into the standard Z8 register file, the software can treat the counter/timer as a gen-
eral-purpose register, thus eliminating the requirement for special instructions.
PS010504-1002
PRELIMINARY