CDP1879 Intersil Corporation, CDP1879 Datasheet - Page 15

• Manufacturer Part Number: CDP1879
• Description: CMOS Real-Time Clock
• Manufacturer: Intersil Corporation

FIGURE 12. CDP1800 SERIES MEMORY MAPPED WRITE CYCLE TIMING WAVEFORMS
FIGURE 13. CDP1800 SERIES MEMORY MAPPED READ CYCLE TIMING WAVEFORMS
MEMORY
REAL TIME CLOCK
TO REAL TIME CLOCK
FIGURE 14. TYPICAL CDP1802 INPUT/OUTPUT MAPPED SYSTEM
DATA FROM CPU
DATA FROM
ADDRESS
TO CPU
ADDRESS
ADDRESS
TPA
TPB/WR
RD
LINES
TPA
CDP1879, CDP1879C-1
HIGH BYTE
INTERRUPT
CDP1802
HIGH BYTE
CLEAR
MRD
TPB
TPA
ENABLED
N0
N1
N2
4-118
OUTPUT DRIVERS
LATCH HIGH-ORDER
ADDRESS FOR CS
VALID DATA
VALID DATA
LOW BYTE
DISABLED
LOW BYTE
RESET
TPA
RD
TPB/WR
INTERRUPT
A0
A1
A2
XTAL
DB0 - DB7
CDP1879
DATA LATCHED
IO/MEM
CLOCK
OUT
XTAL
CS
V
DD