ST9 datasheet(32/146 Pages) STMICROELECTRONICS

32 / 146 page

32/146

ST9 USER GUIDE

Figure 14

. Stack Location Options

3.3 INSTRUCTION SET

The ST9 is said to be an 8/16-bit microcontroller. This means that although the size of the in-

ternal registers and the width of the data bus are 8 bits, the instruction set includes instructions

that handle a pair of registers or a pair of bytes in memory at once. These instructions repre-

sent roughly one half of the total instructions, which means that the ST9 can be programmed

with the same ease as if it were advertised as a full 16-bit device.

This is why it is well suited for C programming, as illustrated in this book.

Data Memory

(RAM)

Bottom

of Stack

Group E

System Registers

Group F

Paged Registers

R255

R240

R239

R00

Stack Pointer Low

Stack Pointer High

R255

R240

R239

R00

Bottom

of Stack

Group E

System Registers

Group F

Paged Registers

Stack Pointer Low

Stack Pointer High

Stack

System or User Stack

in Data Memory Space

System or User Stack

in Register Space

High byte of pointer irrelevant

ST9 データシート(PDF) 32 Page - STMicroelectronics

ST9 データシート(HTML) 32 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

データシートダウンロード