HDSP-2301 HP [Agilent(Hewlett-Packard)], HDSP-2301 Datasheet - Page 28

• Manufacturer Part Number: HDSP-2301
• Description: Four Character 5.0 mm (0.20 inch) 5 x 7 Alphanumeric Displays
• Manufacturer: HP [Agilent(Hewlett-Packard)]

WR (6800 OR
8080A INTERFACE)
INTERFACE ONLY)
Figure 14. Memory Write Timing for the 32 Character HDSP-2000 CODED DATA CONTROLLER
Figure 15. Timing Information for the 32 Character HDSP-2000 CODED DATA CONTROLLER
can either test the flag or allow
the flag to automatically interrupt
the microprocessor. Subroutine
“READ” would then be used to
read the DATA OUT outputs from
the controller into the micropro-
cessor system. The
microprocessor uses the CB
input of the 6821 PIA to determine
when to read each of the 34 data
output words into the system.
DISPLAY
CLOCK
(Z-80
CHIP SELECT
ADDRESS
1
2
3
4
DATA
COLUMNS
(LOAD)
OFF
ROW 1
0
t CW
ROW 2
t AW
1
1
ROW 3 ROW 4 ROW 5 ROW6 ROW 7
2
CHARACTER 1
COLUMNS ON
t WC
A similar PIA interface for the
8080A microprocessor is depicted
in Figures 22 and 23.
The HDSP-247X series of control-
lers are programmed to default to
“Left Entry” mode for a 32 charac-
ter string of displays. If some
other entry mode or string length
is desired, it is necessary to either
load the appropriate control word
from the microprocessor or to
3
t WP
4
t DW
5
224 CLOCK CYCLES
224 CLOCK CYCLES
t CH
t DH
6
t WR
COLUMNS
(LOAD)
OFF
ROW 1 ROW 2 ROW 3 ROW 4
0
1
CHARACTERS 2—32
2
COLUMNS ON
WRITE CYCLE
WRITE DELAY
CHIP ENABLE TO WRITE
DATA SETUP
DATA HOLD
WRITE PULSE
WRITE RECOVERY
CHIP ENABLE HOLD
provide a control word during
POWER ON RESET. The control-
ler will read the DATA IN lines
during RESET and interpret the
contents as the control word. The
circuit depicted in Figure 24 can
be utilized to load any desired
preprogrammed word into the
HDSP247X controller, during
power on.
20
PARAMETER
3
4
ROW 6 ROW 7
5
6
SYMBOL
COLUMNS
t WC
t AW
t CW
t DW
t WP
t WR
t DH
t CH
(LOAD)
OFF
AN1016.15
390 ns
220 ns
310 ns
65 ns
65 ns
20 ns
10 ns
20 ns
MIN.
AN1016.14