18.1.1
Block Diagram
Figure 18.1 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'F77E
H'F77F
Even address
Odd address
Figure 18.1 Block Diagram of On-Chip ROM (H8/3337Y Single-Chip Mode)
Writer Mode (H8/3337Y, H8/3334Y)
Writer Mode Setup
18.2
18.2.1
In writer mode the PROM versions of the H8/3337Y and H8/3334Y suspend the usual
microcomputer functions to allow the on-chip PROM to be programmed. The programming
method is the same as for the HN27C101, except that page programming is not supported.
To select writer mode, apply the signal inputs listed in table 18.2.
Table 18.2 Selection of Writer Mode
Pin
Input
Low
Low
Low
High
Mode pin MD1
Mode pin MD0
STBY pin
Pins P63 and P64
362
RENESAS [ RENESAS TECHNOLOGY CORP ]
