Toshiba TLCS-900/L1 Series Manual page 114

3.8 External Memory Extension Function (MMU)
This is MMU function which can expand program/data area to 106 Mbytes by having 4 local
areas.
Address pins to external memory are 2 extended address bus pins (EA24, EA25) and 8
extended chip select pins (
are common specification of TLCS-900 family and 4 chip select pins (
CS/WAIT controller.
The feature and the recommendation setting method of two types are shown below.
In addition, AH in the table is the value which number address 23 to 16 displayed as hex.
Purpose
Program ROM
Data ROM
Option program ROM
Data RAM
Extended memory 1
Total memory size
to ) in addition to 24 address bus pins (A0 to A23) which
CS2A CS2E
Item
Maximum memory size
Used local area, BANK number
Setting CS/WAIT
Used pin
CS
Maximum memory size
Used local area, BANK number
Setting CS/WAIT
Used pins
CS
Maximum memory size
Used local area, BANK number
Setting CS/WAIT
Used pin
CS
Maximum memory size
Used local area, BANK number
Setting CS/WAIT
Used pin
CS
Maximum memory size
Used local area, BANK number
Setting CS/WAIT
Used pin
CS
91C824-112
(A): For Standard
Extended Memory
2 Mbytes: COMMON2 + 14 Mbytes: bank (16 Mbytes × 1 pcs)
LOCAL2 (AH = C0 − DF: 2 Mbytes × 7 BANK)
Setup AH = C0 − FF to CS2
CS2
64 Mbytes (64 Mbytes × 1 pcs)
LOCAL3 (AH = 80 − BF:
4 Mbytes × 16 BANK)
Setup AH = 80 − BF to CS3
, EA24, EA25
CS3
2 Mbytes: COMMON1 + 14 Mbytes : bank (16 Mbytes × 1 pcs)
LOCAL1 (AH = 40 − 5F: 2 Mbytes × 7 BANK)
Setup AH = 40 − 7F to CS1
CS1
1 Mbyte : COMMON0 + 7 Mbytes: bank (8 Mbytes × 1 pcs)
LOCAL0 (AH = 10 − 1F: 1 Mbyte × 7 BANK)
Setup AH = 00 − 3F to CS0
CS0
COMMON0α
Overlapped data RAM
Setup AH = 00 − 3F to CS0
CS0
16M + 64M + 16M + 8M = 104
Mbytes
TMP91C824
to ) output from
CS0 CS3
(B): For Many Pieces
Extended Memory
Setup AH = 80 − FF to CS2
CS2A
64 Mbytes (16 Mbytes × 4 pcs)
LOCAL3 (AH = 80 − BF:
4 Mbytes × 16 BANK)
Setup AH = 80 − FF to CS2
, , ,
CS2B CS2C CS2D CS2E
Setup AH = 00 − 1F to CS3
CS3
2 Mbytes (2 Mbytes × 1 pcs)
None
Setup AH = 20 − 3F to CS0
CS0
16M + (16M + 16M + 16M +
16M) + 16M + 8M + 2M = 106
Mbytes
2008-02-20