Bit Bus Single Read (32-Bit Word) Operation (Rom/Sram) - Toshiba TX39 Series User Manual

TOSHIBA
9.5.2

16-bit bus single read (32-bit word) operation (ROM/SRAM)

(1) ROM and SRAM other than page mode MROM
S 0
G C L K ( 5 0 M H z )
A[31:1]
BE[3:0]*
C E n m *
O E n *
S W E *
( S R A M O n l y )
D[15:0]
Fig. 9-13
(2) Page mode MROM
S 0
S Y S C L K
A[31:1]
B E [ 3 : 0 ] *
C E n m *
O E n *
S W E *
( S R A M O n l y )
D[15:0]
Fig. 9-14
When a 16-bit page mode MROM is used to read a 32-bit word, the access is conducted in the
page mode. The built-in page counter is not used in the single read operation.
1 s t R e a d C y c l e ( 4 W a i t )
S 1 S W S W S W
S W
4 n + 0
H H L L
t C E
16-bit Bus Memory Single Read (Word) Operation
(Other Than Page Mode MROM)
1 s t R e a d C y c l e ( 4 W a i t )
S 1 S W S W
S W
4 n + 0
H H L L
t C E
16-bit Bus Memory Single Read (Word) Operation
(Page Mode MROM)
101
TMPR3904F Rev. 2.0
2 n d R e a d C y c l e ( 4 W a i t )
S 3 S 4 S 0 S W
S W
D a t a
2 n d R e a d C y c l e ( 1 W a i t )
S W S 3 S 4 S P 0
S P W
D a t a
t P A C
S W S W S 3 S 4 S 0
4 n + 2
H H L L
D a t a
t A C C
S P 3 S P 4 S 0
4 n + 2
H H L L
D a t a