Toshiba TLCS-90 Series Data Book page 212

TOSHIBA
TMP90C840
Memory
CPU
I
A 03
1 1
1
1
89 2003H
B
89
1<-1------
1
HL
1
2
0 0 0
1
1
"89H" in the memory address 2003H is loaded into Register B. In this
mode, the data in Register A are considered as 8-bit signed number,
and the displacement value ranges from -128 to +127.
(6) Extended addressing mode
In this mode, the operand is accessed by 2-byte (16-bit) data in the
opcode.
Example: LD A, (2000H)
Memory
CPU
1
.-..,;.4.;;,...5
_I <-1------
1 1
A
45 2000H
1
I
1
-------------------1
"45H" in the memory address 2000H is loaded into Register A.
(7) Direct addressing mode
The operand in this mode is located in a memory address from FFOOH to
FFFFH specified by I-byte (8 bits) data in the opcode. Compared with
the extended addressing mode, it saves both program memory and
executing time. This mode allows the access to 256-byte addresses
from FFOOH to FFFFH •
• or the TMP90C840, this direct area is divided into the internal RAM
(192 bytes from FFOOH to FFBFH) and the internal I/O area (48 bytes
from FFCOH to FFEFH).
MPU90-14