
741
Section 23 RAM
23.1
Overview
The SH7040 series has 4 kbytes of on-chip RAM. The on-chip RAM is linked to the CPU and
direct memory access controller (DMAC)/data transfer controller (DTC) with a 32-bit data bus
(figure 23.1). The CPU can access data in the on-chip RAM in 8, 16, or 32 bit widths. The DMAC
can access 8 or 16 bit widths. On-chip RAM data can always be accessed in one state, making the
RAM ideal for use as a program area, stack area, or data area, which require high-speed access.
The contents of the on-chip RAM are held in both the sleep and standby modes. Memory area 0
addresses H'FFFFF000–H'FFFFFFFF are allocated to the on-chip RAM.
H'FFFFF000
H'FFFFF004
H'FFFFF001
H'FFFFF005
H'FFFFF002
H'FFFFF006
H'FFFFF003
H'FFFFF007
H'FFFFFFFC
H'FFFFFFFD
H'FFFFFFFE
H'FFFFFFFF
On-chip RAM
Internal data bus (32 bits)
Figure 23.1 Block Diagram of RAM
23.2
Operation
The on-chip RAM is accessed by accessing addresses H'FFFFF000–H'FFFFFFFF. On-chip RAM
is also used as cache memory. There are 2 kbytes of on-chip RAM space during cache use. See
section 9, Cache Memory (CAC), for details.
Summary of Contents for SH7041 Series
Page 2: ......
Page 6: ......
Page 38: ...xvi ...
Page 44: ...6 ...
Page 46: ...8 ...
Page 48: ...10 ...
Page 82: ...44 ...
Page 114: ...76 ...
Page 118: ...80 ...
Page 124: ...86 ...
Page 170: ...132 ...
Page 250: ...212 ...
Page 492: ...454 ...
Page 506: ...468 ...
Page 604: ...566 ...
Page 684: ...646 ...
Page 706: ...668 ...
Page 778: ...740 ...
Page 780: ...742 ...
Page 818: ...780 ...
Page 850: ...812 ...
Page 923: ...SH7040 SH7041 SH7042 SH7043 SH7044 SH7045 Group Hardware Manual REJ09B0044 0600O ...