z86e54 ZiLOG Semiconductor, z86e54 Datasheet - Page 33

• Manufacturer Part Number: z86e54
• Description: Z8 512 Byte Otp Mcu
• Manufacturer: ZiLOG Semiconductor

PS020102-1003
F8h
F7h
F6h
F5h
F4h
F3h
F2h
F1h
Note: Registers are not reset after a Stop-Mode Recovery using P27 pin. A subsequent reset causes
Address Register D7 D6 D5 D4 D3 D2 Dl D0
Program Memory
these control registers to be reconfigured as indicated in Table 14 and the user must avoid bus
contention on the port pins or it may affect device reliability
A timer circuit clocked by a dedicated on-board RC oscillator is used for a POR
timer function. The POR time allows V
before instruction execution begins. The POR timer circuit is a one-shot timer trig-
gered by one of the four following conditions:
•
•
•
•
Watch-Dog Timer Reset
The WDT is a retriggerable one-shot timer that resets the Z8
minal count. The WDT is initially enabled by executing the WDT instruction and is
retriggered on subsequent execution of the WDT instruction. The timer circuit is
driven by an on-board RC oscillator.
The Z86E54 addresses up to 512B of internal program memory (Figure 13). The
first 12 bytes of program memory are reserved for the interrupt vectors. These
locations contain six 16-bit vectors that correspond to the six available interrupts.
Bytes 0–511 are on-chip one-time programmable EPROM.
POW
P3M
P2M
PREO
TO
PREI
T1
TMR
Power-bad to power-good status
Stop-Mode Recovery
WDT time-out
WDH time-out (in Halt mode)
U
U
1
U
U
U
U
0
Table 14. Z8
U
U
1
U
U
U
U
0
U
U
1
U
U
U
U
0
Reset Condition
®
0
U
1
U
U
U
U
0
Control Registers Reset Values*
U
U
1
U
U
U
U
0
1
U
1
U
U
U
U
0
0
0
1
U
U
0
U
0
CC
and the oscillator circuit to stabilize
1
0
1
0
U
0
U
0
Inputs after reset
Comments
Z8
®
®
512 Byte OTP MCU
if it reaches its ter-
Z86E54
27