Renesas rl78 User Manual

RL78/G1A

CHAPTER 3 CPU ARCHITECTURE

R01UH0305EJ0200 Rev.2.00

Jul 04, 2013

3.1.3 Internal data memory space

The RL78/G1A products incorporate the following RAMs.

Table 3-4. Internal RAM Capacity

Part Number

Internal RAM

R5F10ExA (x = 8, B, G)

R5F10ExC (x = 8, B, G, L)

2048

× 8 bits (FF700H to FFEFFH)

R5F10ExD (x = 8, B, G, L)

3072

× 8 bits (FF300H to FFEFFH)

R5F10ExE (x = 8, B, G, L)

4096

× 8 bits (FEF00H to FFEFFH)

The internal RAM can be used as a data area and a program area where instructions are fetched (it is prohibited to use

the general-purpose register area for fetching instructions). Four general-purpose register banks consisting of eight 8-bit

registers per bank are assigned to the 32-byte area of FFEE0H to FFEFFH of the internal RAM area.

The internal RAM is used as stack memory.

Cautions 1. It is prohibited to use the general-purpose register (FFEE0H to FFEFFH) space for fetching

instructions or as a stack area.

2. During self programming and data flash rewriting, the stack, data buffer, and RAM addresses

used as branch destinations for vectored interrupts or as sources or destinations of DMA

transfers must not be allocated to the area between addresses FFE20H and FFEDFH.

3. During self programming and data flash rewriting, the RAM area in the products below is

prohibited. Because this area is used for each library.

R5F10ExD (x = 8, B, G, L): FF300H to FF309H

R5F10ExE (x = 8, B, G, L): FEF00H to FF309H