TS80C51RA2 Atmel Corporation, TS80C51RA2 Datasheet - Page 71

• Manufacturer Part Number: TS80C51RA2
• Description: High Performance 8-bit Microcontroller
• Manufacturer: Atmel Corporation

Clock Waveforms
Figure 33. Clock Waveforms
4188A–8051–10/02
MOV DEST PORT (P1, P2, P3)
(INCLUDES INT0, INT1, TO, T1)
WRITE CYCLE
PORT OPERATION
SERIAL PORT SHIFT CLOCK
EXTERNAL PROGRAM MEMORY FETCH
P2 (EXT)
READ CYCLE
MOV DEST P0
INTERNAL
XTAL2
CLOCK
PSEN
ALE
WR
RD
P0
P2
P0
P0
P2
TXD (MODE 0)
SAMPLED
FLOAT
DATA
STATE4
P1P2
PCL OUT
DPL OR Rt OUT
INDICATES ADDRESS TRANSITIONS
DPL OR Rt OUT
Valid in normal clock mode. In X2 mode XTAL2 signal must be changed to XTAL2
divided by two.
This diagram indicates when signals are clocked internally. The time it takes the signals
to propagate to the pins, however, ranges from 25 to 125 ns. This propagation delay is
dependent on variables such as temperature and pin loading. Propagation also varies
from output to output and component. Typically though (T
WR propagation delays are approximately 50ns. The other signals are typically 85 ns.
Propagation delays are incorporated in the AC specifications.
P1P2
STATE5
P0 PINS SAMPLED
INDICATES DPH OR P2 SFR TO PCH TRANSITION
RXD SAMPLED
P1, P2, P3 PINS SAMPLED
OLD DATA
P1P2
STATE6
INDICATES DPH OR P2 SFR TO PCH TRANSITION
SAMPLED
FLOAT
DATA
NEW DATA
P1P2
STATE1
PCL OUT
P1P2
STATE2
THESE SIGNALS ARE NOT ACTIVATED DURING THE
EXECUTION OF A MOVX INSTRUCTION
DATA OUT
FLOAT
P1, P2, P3 PINS SAMPLED
P1P2
STATE3
FLOAT
SAMPLED
DATA
P1P2
PCL OUT (EVEN IF PROGRAM
MEMORY IS INTERNAL)
STATE4
PCL OUT (IF PROGRAM
MEMORY IS EXTERNAL)
PCL OUT
PCL OUT (IF PROGRAM
MEMORY IS EXTERNAL)
A
P1P2
=25°C fully loaded) RD and
STATE5
P0 PINS SAMPLED
TS8xC51Rx2
RXD SAMPLED
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