cdp6402 Harris Corporation, cdp6402 Datasheet - Page 11

• Manufacturer Part Number: cdp6402
• Description: Cmos Universal Asynchronous Receiver/transmitter Uart
• Manufacturer: Harris Corporation

NOTES:
NOTES:
1. The holding register is loaded on the trailing edge of TBRL.
2. The transmitter shift register, if empty , is loaded on the first high-to-low transition of the clock which occurs at least 1/2 clock period +
1. If a start bit occurs at a time less than t
2. If a pending DA has not been cleared by a read of the receiver holding register by the time a new word is loaded into the receiver holding
t
high-to-low transition of the clock. The start bit may be completely asynchronous with the clock.
register, the OE signal will come true..
THC
after the trailing edge of TBRL and transmission of a start bit occurs 1/2 clock period + t
R BUS 0 -
(NOTE 2)
R BUS 7
RRC
DRR
RRI
T BUS 0
T BUS 7
DR
OE
PE
FE
(NOTE 1)
t
TBRE
CH
TBRL
TRO
TRC
TRE
t
DC
t
CC
t
CL
1
t
CH
2
t
THC
t
t
t
TTHR
THTH
CC
t
DC
DT
FIGURE 7. TRANSMITTER TIMING WAVEFORMS
3
START BIT PARITY
t
DATA
FIGURE 8. RECEIVER TIMING WAVEFORMS
CL
before a high-to-low transition of the clock, the start bit may not be recognized until the next
4
CLOCK 7 1/2
t
DT
CDP6402, CDP6402C
SAMPLE
5
t
t
DDA
DD
1
TRANSMITTER BUFFER
REGISTER LOADED
(NOTE 1)
TRANSMITTER SHIFT
REGISTER LOADED
(NOTE 2)
t
6
TTS
2
t
CD
t
7
CT
5-84
3
16
4
STOP BIT 1
1
5
2
6
HOLDING REGISTER
3
CLOCK 7 1/2 LOAD
7
4
14
CD
5
15
later.
t
COE
6
t
t
CPE
16
CFE
7
1
1ST DATA BIT
8
2
t
CD
DATA
9
t
t
CDA
CDV
3