HD6433308 Datasheet, PDF (252/349 Pages) Hitachi Semiconductor – Hitachi Single-Chip MicroComputer

13.1.1 Block Diagram
Figure 13-1 is a block diagram of the on-chip ROM.
Internal data bus (upper 8 bits)
Internal data bus (lower 8 bits)
H'0000
H'0002
H'0001
H'0003
On-chip ROM
H'3FFE
H'3FFF
Even addresses Odd addresses
Figure 13-1. Block Diagram of On-Chip ROM
13.2 PROM Mode
13.2.1 PROM Mode Setup
In the PROM mode of the PROM version of the H8/330, the usual microcomputer functions are
halted to allow the on-chip PROM to be programmed. The programming method is the same as for
the HN27C256.
To select the PROM mode, apply the signal inputs listed in Table 13-2.
Table 13-2. Selection of PROM Mode
Pin
Mode pin MD1
Mode pin MD0
STBY pin
Pins P80 and P81
Input
Low
Low
Low
High
242