2
Table 1-1 Features
Feature
Description
CPU
Upward-compatible with the H8/300 CPU at the object-code level
General-register machine
•
Sixteen 16-bit general registers
(also useable as sixteen 8-bit registers or eight 32-bit registers)
High-speed operation
•
Maximum clock rate: 18 MHz
•
Add/subtract: 111 ns
•
Multiply/divide: 778 ns
Two CPU operating modes
•
Normal mode (64-kbyte address space)
*
•
Advanced mode (16-Mbyte address space)
Instruction features
•
8/16/32-bit data transfer, arithmetic, and logic instructions
•
Signed and unsigned multiply instructions (8 bits
×
8 bits, 16 bits
×
16 bits)
•
Signed and unsigned divide instructions (16 bits
÷
8 bits, 32 bits
÷
16 bits)
•
Bit accumulator function
•
Bit manipulation instructions with register-indirect specification of bit positions
Memory
H8/3022
•
ROM: 256 kbytes
•
RAM: 8 kbytes
H8/3021
•
ROM: 192 kbytes
•
RAM: 8 kbytes
H8/3020
•
ROM: 128 kbytes
•
RAM: 4 kbytes
Interrupt
•
Five external interrupt pins: NMI,
IRQ
0
,
IRQ
1
,
IRQ
4
,
IRQ
5
controller
•
25 internal interrupts
•
Three selectable interrupt priority levels
Bus controller
•
Address space can be partitioned into eight areas, with independent bus
specifications in each area
•
Two-state or three-state access selectable for each area
•
Selection of four wait modes