M16C80 Datasheet, PDF (195/358 Pages) Renesas Technology Corp – RENESAS 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/80 SERIES

M16C/80 Group
25. DRAM Controller
• DRAM Controller Multiplex Address Output
The DRAM controller outputs the row addresses and column addresses as a multiplexed signal to the
address bus A8 to A20. Figure 25.2 shows the output format for multiplexed addresses.
8-bit bus mode
Pin function
Row address
MA12 MA11 MA10 MA9 MA8 MA7 MA6 MA5 MA4 MA3 MA2 MA1 MA0
(A20) (A19) (A18) (A17) (A16) (A15) (A14) (A13) (A12) (A11) (A10) (A9) (A8)
(A20) (A19) A18 A17 A16 A15 A14 A13 A12 A11 A10 A9
–
Column address ^{(A22) (A22) A19 A8 A7 A6 A5 A4 A3 A2 A1 A0}
–
512KB, 1MB
Row address
(A20) A19 A18 A17 A16 A15 A14 A13 A12 A11 A10 A9
–
Column address ^{(A22) A21 A20 A8 A7 A6 A5 A4 A3 A2 A1 A0}
–
2MB, 4MB
Row address
A20 A19 A18 A17 A16 A15 A14 A13 A12 A11 A10 A9
–
Column address (A22) ^{A22 A21} A8 ^{A7 A6 A5 A4 A3 A2 A1 A0}
–
8MB
16-bit bus mode
Pin function
MA12 MA11 MA10 MA9 MA8 MA7 MA6 MA5 MA4 MA3 MA2 MA1 MA0
(A20) (A19) (A18) (A17) (A16) ^(A15) (A14) (A13) (A12) (A11) (A10) (A9) (A8)
Row address
(A20) (A19) A18 A17 A16 A15 A14 A13 A12 A11 A10 (A9) –
Column address ^{(A22) (A20) A9 A8 A7 A6 A5 A4 A3 A2 A1 (A0) –}
512KB
Row address
(A20) A19 A18 A17 A16 A15 A14 A13 A12 A11 A10 (A9) –
Column address ^{(A22) A20 A9}
A8
A7
A6
A5
A4 A3
A2
A1 (A0)
–
1MB, 2MB
Row address
A20 A19 A18 A17 A16 A15 A14 A13 A12 A11 A10 (A9) –
Column address A22 ^A21 A9 A8 A7 A6 A5 A4 A3 A2 ^A1 (A0) –
4MB, 8MB ^{(Note 2)}
Note 1: ( ) invalid bit:
bits that change according to selected mode (8-bit/16-bit bus mode, DRAM
space).
Note 2: The figure is for 4Mx1 or 4Mx4 memory configuration. If you are using a 4Mx16 configuration,
use combinations of the following: For row addresses, MA0 to MA12; for column addresses
MA2 to MA8, MA11, and MA12. Or for row addresses MA1 to MA12; for column addresses
MA2 to MA9, MA11, MA12.
Note 3: "–" is indeterminate.
Figure 25.2 Output format for multiplexed addresses
Rev.1.00 Aug. 02, 2005 ^{Page 184} of 329
REJ09B0187-0100