CHAPTER 4 BUS CONTROL FUNCTION
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User’s Manual U14359EJ4V0UM
(2) Address setup wait control register (ASC)
The V850E/MA1 allows insertion of address setup wait states before the SRAM/page ROM cycle (the setting
of the ASC register in the EDO DRAM/SDRAM cycle is invalid).
The number of address setup wait states can be set with the ASC register for each CS space.
This register can be read/written in 16-bit units.
Cautions 1. During an address setup wait, the WAIT pin-based external wait function is disabled.
2. Write to the ASC register after reset, and then do not change the set value.
15
AC71
ASC
CSn signal
Address
FFFFF48AH
After reset
FFFFH
14
AC70
13
AC61
12
AC60
11
AC51
10
AC50
9
AC41
8
AC40
7
AC31
6
AC30
5
AC21
4
AC20
3
AC11
2
AC10
1
AC01
0
AC00
CS3
CS2
CS1
CS0
CS4
CS5
CS6
CS7
Bit position
Bit name
Function
Address Cycle
Specifies the number of address setup wait states inserted before the SRAM/page ROM
cycle for each CS space.
ACn1
ACn0
Number of wait states
0
0
Not inserted
0
1
1
1
0
2
1
1
3
15 to 0
ACn1, ACn0
(n = 0 to 7)