CHAPTER 5 MEMORY ACCESS CONTROL FUNCTION
User’s Manual U12688EJ4V0UM00
130
5.2
Page ROM Controller (ROMC)
The page ROM controller (ROMC) is for access to ROM (page ROM) with a page access function.
Comparison of addresses with the immediately previous bus cycle is carried out and wait control for normal access
(off-page) and page access (on-page) is executed. This controller is capable of handling page widths of from 8 to 64
bytes.
5.2.1 Features
•
It can connect directly to 8-bit/16-bit page ROM.
•
When the bus width is 16 bits, it can handle 4/8/16/32-word page access.
When the bus width is 8 bits, it can handle 8/16/32/64-word page access.
•
Individual wait settings (0 to 7 waits) for off-page and on-page are possible.
5.2.2 Page ROM connections
Examples of page ROM connections are shown below.
Figure 5-3. Example of Page ROM Connections (1/2)
(a) In the case of 16 Mbit (1 M
××××
16) page ROM
V
DD
A1 to A20
D0 to D15
RD
CSn
V850E/MS1
16 Mbit page-ROM (1 M
×
16)
A0 to A19
O1 to O16
WORD/BYTE
OE
CE
Remark
n = 0 to 7
Содержание V850E/MS1 UPD703100
Страница 2: ...User s Manual U12688EJ4V0UM00 2 MEMO ...
Страница 6: ...User s Manual U12688EJ4V0UM00 6 MEMO ...
Страница 8: ...User s Manual U12688EJ4V0UM00 8 MEMO ...
Страница 12: ...User s Manual U12688EJ4V0UM00 12 MEMO ...
Страница 26: ...User s Manual U12688EJ4V0UM00 26 MEMO ...
Страница 68: ...User s Manual U12688EJ4V0UM00 68 MEMO ...
Страница 124: ...User s Manual U12688EJ4V0UM00 124 MEMO ...
Страница 198: ...User s Manual U12688EJ4V0UM00 198 MEMO ...
Страница 230: ...User s Manual U12688EJ4V0UM00 230 MEMO ...
Страница 422: ...User s Manual U12688EJ4V0UM00 422 MEMO ...