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CHAPTER 26
µ
PD78P054, 78P058
Address InputA0-A16
CE (Input)
OE (Input)
D0-D7 Hi-Z Data Output Hi-Z
26.4.3 PROM reading procedure
PROM contents can be read onto the external data bus (D0 to D7) using the following procedure.
(1) Fix the RESET pin low, and supply +5 V to the VPP pin. Unused pins are handled as shown in paragraph,
(2) “PROM programming mode” in section 1.5 or 2.5 Pin Configuration (Top View).
(2) Supply +5 V to the VDD and VPP pins.
(3) Input the address of data to be read to pins A0 through A16.
(4) Read mode is entered.
(5) Data is output to pins D0 through D7.
The timing for steps (2) through (5) above is shown in Figure 26-8.
Figure 26-8. PROM Read Timing