Z90102 Datasheet, PDF (32/36 Pages) Zilog, Inc. – 40-Pin Low-Cost Digital Television Controller

Z90102/90103/90104
40-Pin Low-Cost Digital Television Controller
Z8 REGISTER DIAGRAMS (Continued)
Zilog
R244 T0
F4H
D7 D6 D5 D4 D3 D2 D1 D0
T0 Initial Value
(When Written)
(Range: 1-256 Decimal
01-00 Hex)
T0 Current Value
(When Read)
Figure 57. Counter/Timer 0 Register
(F4H: Read/Write)
R245 PRE0
F5H
D7 D6 D5 D4 D3 D2 D1 D0
* Default After Reset
Count Mode
0 T0 Single Pass*
1 T0 Modulo-N
Reserved (Must be 0)
Prescaler Modulo
(Range: 1-64 Decimal
01-00 Hex)
Figure 58. Prescaler 0 Register
(F5H: Write Only)
R246 P2M
F6H
D7 D6 D5 D4 D3 D2 D1 D0
P27 - P20 I/O Definition
0 Defines Bit as Output
1 Defines Bit as Input
Figure 59. Port 2 Mode Register
(F6H: Write Only)
R247 P3M
F7H
D7 D6 D5 D4 D3 D2 D1 D0
0 - Port 2 Open-Drain
1 - Port 2 Push-Pull
Reserved (Must be 0)
0 P32 - Input P35 - Output
(Must be 0)
00 P33 - Input P34 - Output
(Must be 0)
11 Reserved
0 P31 - Input (TIN) P36 - Output (TOUT)
0 P30 - Input
Reserved (Must be 0)
Figure 60. Port 3 Mode Register
(F6H; Write Only)
R249 IPR
F9H
D7 D6 D5 D4 D3 D2 D1 D0
Interrupt Group Priority
000 Reserved
001 C > A > B
010 A > B > C
011 A > C > B
100 B > C > A
101 C > B > A
110 B > A > C
111 Reserved
IRQ1, IRQ4 Priority (Group C)
0 IRQ1 > IRQ4
1 IRQ4 > IRQ1
IRQ1, IRQ2 Priority (Group B)
0 IRQ2 > IRQ0
1 IRQ0 > IRQ2
IRQ3, IRQ5 Priority (Group A)
0 IRQ5 > IRQ3
1 IRQ3 > IRQ5
Reserved (Must be 0)
Figure 61. Interrupt Priority Register
(F9H: Write Only)
32
DS97TEL1902