ST7FOXK1 STMicroelectronics, ST7FOXK1 Datasheet - Page 178

• Manufacturer Part Number: ST7FOXK1
• Description: Low cost flash 8bit micro
• Manufacturer: STMicroelectronics

Specifications of ST7FOXK1

• 4 To 8 Kbytes Single Voltage Extended Flash (xflash) Program Memory With Read-out Protection In-circuit Programming And In-application Programming (icp And Iap) Endurance: 1K write/erase cycles guaranteed Data retention
• Clock Sources: Internal trimmable 8 MHz RC oscillator, auto wakeup internal low power - low frequency oscillator, crystal/ceramic resonator or external clock
• Five Power Saving Modes: Halt, Active-Halt, Auto Wakeup from Halt, Wait and Slow
• A/d Converter: up to 10 input channels

Instruction set
11
11.1
Table 59.
178/226
Immediate
No Offset
Inherent
Short
Short
Short
Short
Long
Long
Long
Instruction set
ST7 addressing modes
The ST7 core features 17 different addressing modes which can be classified in seven main
groups:
Table 58.
The ST7 instruction set is designed to minimize the number of bytes required per
instruction: To do so, most of the addressing modes may be subdivided in two submodes
called long and short:
The ST7 Assembler optimizes the use of long and short addressing modes.
ST7 addressing mode overview
Mode
Indirect
Indirect
Indirect
Direct
Direct
Direct
Direct
Direct
Long addressing mode is more powerful because it can use the full 64 Kbyte address
space, however it uses more bytes and more CPU cycles.
Short addressing mode is less powerful because it can generally only access page
zero (0000h - 00FFh range), but the instruction size is more compact, and faster. All
memory to memory instructions use short addressing modes only (CLR, CPL, NEG,
BSET, BRES, BTJT, BTJF, INC, DEC, RLC, RRC, SLL, SRL, SRA, SWAP)
Description of addressing modes
Indexed
Indexed
Indexed
Indexed
Addressing mode
Bit operation
Immediate
Inherent
Relative
Indexed
Indirect
Direct
ld A,($1000,X)
ld A,([$10],X)
ld A,($10,X)
ld A,[$10.w]
ld A,$1000
ld A,#$55
ld A,[$10]
ld A,$10
ld A,(X)
Syntax
nop
Destination/
0000..FFFF
0000..FFFF
0000..FFFF
00..1FE
00..1FE
source
00..FF
00..FF
00..FF
address
Pointer
00..FF
00..FF
00..FF
ST7FOXF1, ST7FOXK1, ST7FOXK2
ld A,([$55],X)
bset
ld A,($55,X)
ld A,#$55
Pointer
ld A,$55
Example
jrne loop
word
size
byte
byte
nop
byte,#5
+ 0 (with X register)
+ 1 (with Y register)
Length
(bytes)
+ 0
+ 1
+ 1
+ 2
+ 1
+ 2
+ 2
+ 2
+ 2