Z86C04 Datasheet, PDF (21/34 Pages) Zilog, Inc. – CMOS 8-BIT LOW-COST 1K/2K-ROM MICROCONTROLLERS

Zilog
Z86C04/C08
CMOS 8-Bit Low-Cost 1K/2K-ROM Microcontrollers
FUNCTIONAL DESCRIPTION
RESET. Upon power-up the Power-On Reset circuit waits execution at address%000C (Hex) (Figure 10). The device
for T_POR ms, plus 18 clock cycles, and then starts program control registers’ reset value is shown in Table 2.
1
POR
(Cold Start)
P27
(Stop Mode)
INT OSC
Delay Line
TPOR ms
XTAL OSC
18 CLK
Reset Filter
Chip
Reset
Figure 9. Internal Reset Configuration
Addr.
03H (3)*
02H (2)*
00H (0)*
FFH(255)
FFH (254)
FDH (253)
FCH (252)
FBH (251)
FAH (250)
Reg.
Port 3
Port 2
Port 0
SPL
GPR
RP
FLAGS
IMR
IRQ
Table 1. Z86C04/C08 & C05/C07 Control Registers
Reset Condition
D7
D6 D5 D4 D3
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
U
U
U
U
U
0
U
U
U
U
U
U
0
0
0
D2
D1
U
U
U
U
U
U
0
0
0
0
0
0
U
U
U
U
0
0
F9H (249)
F8H (248)*
F7H (247)*
F6H (246)*
IPR
P01M
P3M
P2M
U
U
U
U
U
U
U
U
0
U
U
U
U
U
U
1
1
1
1
1
U
U
U
0
U
0
1
1
F5H (245)
PRE0
U
U
U
U
U
U
U
F4H (244)
T0
U
U
U
U
U
U
U
F3H (243)
PRE1
U
U
U
U
U
U
0
F2H (242)
T1
U
U
U
U
U
U
U
F1H (241)
TMR
0
0
0
0
0
0
0
Note: *Registers are not reset after a STOP-Mode Recovery using P27 pin.
A subsequent reset will cause these control registers to be re-configured as shown in
Table 2 and the user must avoid bus contention on the port pins or it may affect device reliability.
D0
Comments
U
U
U
0
0
0
U
U
0
IRQ3 is used
for positive
edge detection
U
1
0
1
Inputs after
reset
0
U
0
U
0
DS97DZ80502
PRELIMINARY
21