82C55A Intersil Corporation, 82C55A Datasheet - Page 20

• Manufacturer Part Number: 82C55A
• Description: CMOS Programmable Peripheral Interface
• Manufacturer: Intersil Corporation

Timing Waveforms
NOTE: Any sequence where WR occurs before ACK and STB occurs before RD is permissible. (INTR = IBF MASK STB RD OBF
PERIPHERAL
OUTPUT
MASK ACK WR)
INTR
OBF
ACK
INTR
OBF
ACK
BUS
STB
WR
WR
IBF
RD
CPU TO 82C55A
DATA FROM
(Continued)
tWIT
(28)
PERIPHERAL TO 82C55A
FIGURE 28. MODE 1 (STROBED OUTPUT)
tWOB
(21)
FIGURE 29. MODE 2 (BI-DIRECTIONAL)
DATA FROM
tPS (17)
82C55A
tSIB
(23)
tPH (18)
20
(16)
tST
tWB (12)
tWOB (21)
(NOTE)
tAK (15)
82C55A TO PERIPHERAL
tAOB (22)
tAD (19)
DATA FROM
tAK
(15)
tAOB
(22)
tAIT (27)
tKD
(20)
82C55A TO CPU
tRIB (24)
DATA FROM
(NOTE)