
CY7C68013
Document #: 38-08012 Rev. *A
Page 11 of 48
3.9.2
Internal Code Memory, EA = 0
This mode implements the internal eight-kbyte block of RAM (starting at 0) as combined code and data memory. When external
RAM or ROM is added, the external read and write strobes are suppressed for memory spaces that exist inside the chip. This
allows the user to connect a 64-kbyte memory without requiring address decodes to keep clear of internal memory spaces.
Only the internal eight kbytes and scratch pad 0.5 kbytes RAM spaces have the following access:
• USB download
• USB upload
• Setup data pointer
• I
2
C-compatible interface boot load.
Figure 3-1. Internal Code Memory, EA = 0
Inside FX2
Outside FX2
7.5 kbytes
US B regs and
4k EP buffers
(RD#,WR#)
0.5 kbytes RAM
Data (RD#,WR#)*
(OK to populate
data memory
here—RD#/WR#
strobes are not
active)
48 kbytes
External
Data
Memory
(RD#,WR#)
(Ok to populate
data memory
here—RD#/WR#
strobes are not
active)
Eight kbytes RAM
Code and Data
(PSEN#,RD#,WR#)*
56 kbytes
External
Code
Memory
(PSEN#)
(OK to populate
program
memory here—
PSEN# strobe
is not active)
*SUDPTR, USB upload/download, I
2
C-compatible interface boot access
FFFF
E200
E1FF
E000
1FFF
0000
Data
Code