HD64F3437TF16 Datasheet, PDF (390/752 Pages) Hitachi Semiconductor – 12 V must not be applied to the S-mask model (single-power-supply specification), as this may permanently damage the device.

Section 17 RAM
17.1 Overview
The H8/3437 and H8/3436 have 2 kbytes of on-chip static RAM. The H8/3434 has 1 kbyte. The
RAM is connected to the CPU by a 16-bit data bus. Both byte and word access to the on-chip
RAM are performed in two states, enabling rapid data transfer and instruction execution.
The on-chip RAM is assigned to addresses H'F780 to H'FF7F in the address space of the H8/3437
and H8/3436, and addresses H'FB80 to H'FF7F in the address space of the H8/3434. The RAME
bit in the system control register (SYSCR) can enable or disable the on-chip RAM.
17.1.1 Block Diagram
Figure 17.1 is a block diagram of the on-chip RAM.
Internal data bus (upper 8 bits)
Internal data bus (lower 8 bits)
H'F780
H'F782
H'F781
H'F783
On-chip RAM
H'FF7E
H'FF7F
Even address Odd address
Figure 17.1 Block Diagram of On-Chip RAM (H8/3437)
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