.hide-partial { max-height: none; } .show-more { display: none; }

STMicroelectronics Embedded Processors & Controllers

.catnav-wrapper { height: auto; overflow: visible; } .catalog-nav-tabs ul { white-space: normal; }

Types of Embedded Processors & Controllers

List Images

Results: 5,591

Applied Filters:

Manufacturer = STMicroelectronics

Product Type

Mounting Style

Package/Case

Core

Data Bus Width

Maximum Clock Frequency

Program Memory Size

L1 Cache Instruction Memory

L1 Cache Data Memory

Data RAM Size

ADC Resolution

Number of I/Os

Minimum Operating Temperature

Maximum Operating Temperature

Qualification

Packaging

Reset All

Search within results

In Stock

Normally Stocked

Active

New Products

RoHS Compliant

.search-refine-wrapper { display: inline-block; min-width: 100%; } .scroll-body { overflow-x: visible; } .search-table-wrapper { overflow: visible; } .hide-partial { max-height: none; } .show-more { display: none; }

Download Table (.CSV)

Part #

ARM Microcontrollers - MCU 32BIT ARM Cortex M3 Connectivity 1024kB

STM32F205ZGT6
STMicroelectronics
1: €12.56
1,598In Stock

Mfr. Part No.
STM32F205ZGT6

Mouser Part No
511-STM32F205ZGT6

STMicroelectronics

ARM Microcontrollers - MCU 32BIT ARM Cortex M3 Connectivity 1024kB

Learn More

Datasheet

1,598In Stock

€12.56

€10.25

€9.55

€8.97

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-144

ARM Cortex M3

32 bit

120 MHz

1 MB

128 kB

12 bit

114 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU High-performance & DSP FPU, Arm Cortex-M7 MCU 512 Kbytes of Flash 216 MHz CPU, A

STM32F723IET6
STMicroelectronics
1: €13.48
14,987In Stock

Mfr. Part No.
STM32F723IET6

Mouser Part No
511-STM32F723IET6

STMicroelectronics

ARM Microcontrollers - MCU High-performance & DSP FPU, Arm Cortex-M7 MCU 512 Kbytes of Flash 216 MHz CPU, A

Learn More

Datasheet

14,987In Stock

€13.48

€10.68

€9.98

€9.21

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-176

ARM Cortex M7

32 bit

216 MHz

512 kB

256 kB

12 bit

138 I/O

- 40 C

+ 85 C

ARM Microcontrollers - MCU High-performance & DSP FPU, Arm Cortex-M7 MCU 1 Mbyte of Flash 216 MHz CPU, Art

STM32F746IGT6
STMicroelectronics
1: €14.93
5,717In Stock

Mfr. Part No.
STM32F746IGT6

Mouser Part No
511-STM32F746IGT6

STMicroelectronics

ARM Microcontrollers - MCU High-performance & DSP FPU, Arm Cortex-M7 MCU 1 Mbyte of Flash 216 MHz CPU, Art

Learn More

Datasheet

5,717In Stock

€14.93

€12.73

€11.83

€11.17

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-176

ARM Cortex M7

32 bit

216 MHz

1 MB

320 kB

12 bit

140 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU Mainstream Arm Cortex-M0+ MCU 128 Kbytes of Flash 36 Kbytes RAM, 64 MHz CPU, 4x

STM32G071EBY6TR
STMicroelectronics
1: €2.55
14,912In Stock

Mfr. Part No.
STM32G071EBY6TR

Mouser Part No
511-STM32G071EBY6TR

STMicroelectronics

ARM Microcontrollers - MCU Mainstream Arm Cortex-M0+ MCU 128 Kbytes of Flash 36 Kbytes RAM, 64 MHz CPU, 4x

Learn More

Datasheet

14,912In Stock

Cut Tape

€2.55

€1.91

€1.75

€1.57

View

Reel

€1.32

MouseReel Available

Min.: 1
Mult.: 1

Reel: 5,000

ARM Microcontrollers - MCU

SMD/SMT

WLCSP-25

ARM Cortex M0+

32 bit

64 MHz

128 kB

36 kB

12 bit

23 I/O

- 40 C

+ 85 C

Reel, Cut Tape, MouseReel

ARM Microcontrollers - MCU Mainstream Arm Cortex-M4 MCU 170 MHz 512 Kbytes of Flash Math Accel, HR Timer, H

STM32G484QET6
STMicroelectronics
1: €8.68
4,000In Stock

Mfr. Part No.
STM32G484QET6

Mouser Part No
511-STM32G484QET6

STMicroelectronics

ARM Microcontrollers - MCU Mainstream Arm Cortex-M4 MCU 170 MHz 512 Kbytes of Flash Math Accel, HR Timer, H

Learn More

Datasheet

4,000In Stock

€8.68

€6.78

€6.30

€5.78

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-128

ARM Cortex M4

32 bit

170 MHz

512 kB

128 kB

5 x 12 bit

107 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU High-performance & DSP DP-FPU, Arm Cortex-M7 MCU 128 Kbytes of Flash 1MB RAM, 48

STM32H750ZBT6
STMicroelectronics
1: €9.06
2,545In Stock

Mfr. Part No.
STM32H750ZBT6

Mouser Part No
511-STM32H750ZBT6

STMicroelectronics

ARM Microcontrollers - MCU High-performance & DSP DP-FPU, Arm Cortex-M7 MCU 128 Kbytes of Flash 1MB RAM, 48

Learn More

Datasheet

2,545In Stock

€9.06

€7.34

€6.87

€6.49

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-144

ARM Cortex M7

32 bit

480 MHz

128 kB

1 MB

3 x 16 bit

114 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU High-performance Arm Cortex-M7 + Cortex-M4 MCU 2MBytes of Flash 1MB RAM, 480 MHz

STM32H757IIT6
STMicroelectronics
1: €17.21
2,210In Stock

Mfr. Part No.
STM32H757IIT6

Mouser Part No
511-STM32H757IIT6

STMicroelectronics

ARM Microcontrollers - MCU High-performance Arm Cortex-M7 + Cortex-M4 MCU 2MBytes of Flash 1MB RAM, 480 MHz

Learn More

Datasheet

2,210In Stock

€17.21

€13.91

€13.33

€11.75

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-176

ARM Cortex M4, ARM Cortex M7

32 bit

240 MHz, 480 MHz

2 MB

1 MB

3 x 16 bit

128 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU High-performance & DSP DP-FPU, Arm Cortex-M7 MCU 2MBytes of Flash 1376 KB SRAM,

STM32H7A3IIT6Q
STMicroelectronics
1: €14.35
1,936In Stock

Mfr. Part No.
STM32H7A3IIT6Q

Mouser Part No
511-STM32H7A3IIT6Q

STMicroelectronics

ARM Microcontrollers - MCU High-performance & DSP DP-FPU, Arm Cortex-M7 MCU 2MBytes of Flash 1376 KB SRAM,

Learn More

Datasheet

1,936In Stock

€14.35

€10.90

€10.45

€9.21

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-176

Tray

ARM Microcontrollers - MCU Ultra-low-power Arm Cortex-M3 MCU 32 Kbytes of Flash , 32 MHz CPU, USB

STM32L151C6T6A
STMicroelectronics
1: €3.92
12,976In Stock

Mfr. Part No.
STM32L151C6T6A

Mouser Part No
511-STM32L151C6T6A

STMicroelectronics

ARM Microcontrollers - MCU Ultra-low-power Arm Cortex-M3 MCU 32 Kbytes of Flash , 32 MHz CPU, USB

Learn More

Datasheet

12,976In Stock

€3.92

€2.98

€2.74

€2.49

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-48

ARM Cortex M3

32 bit

32 MHz

32 kB

10 kB

12 bit

37 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU Ultra-low-power FPU Arm Cortex-M4 MCU 80 MHz 512 Kbytes of Flash USB OTG, DFSDM

STM32L475RET6TR
STMicroelectronics
1: €6.62
4,388In Stock

Mfr. Part No.
STM32L475RET6TR

Mouser Part No
511-STM32L475RET6TR

STMicroelectronics

ARM Microcontrollers - MCU Ultra-low-power FPU Arm Cortex-M4 MCU 80 MHz 512 Kbytes of Flash USB OTG, DFSDM

Datasheet

4,388In Stock

Cut Tape

€6.62

€5.13

€4.75

€4.33

View

Reel

€3.66

MouseReel Available

Min.: 1
Mult.: 1

Reel: 1,000

ARM Microcontrollers - MCU

SMD/SMT

LQFP-64

ARM Cortex M4

32 bit

80 MHz

512 kB

128 kB

3 x 12 bit

51 I/O

- 40 C

+ 85 C

Reel, Cut Tape, MouseReel

ARM Microcontrollers - MCU Ultra-low-power FPU Arm Cortex-M4 MCU 80 MHz 256 Kbytes of Flash USB OTG, DFSDM

STM32L475VCT6
STMicroelectronics
1: €6.17
5,218In Stock

Mfr. Part No.
STM32L475VCT6

Mouser Part No
511-STM32L475VCT6

STMicroelectronics

ARM Microcontrollers - MCU Ultra-low-power FPU Arm Cortex-M4 MCU 80 MHz 256 Kbytes of Flash USB OTG, DFSDM

Learn More

Datasheet

5,218In Stock

€6.17

€4.43

€4.08

€3.85

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-100

ARM Cortex M4

32 bit

80 MHz

256 kB

128 kB

3 x 12 bit

82 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU Ultra-low-power FPU Arm Cortex-M4 MCU 80 MHz 1 Mbyte of Flash USB OTG, LCD, AES-

STM32L4A6VGT6
STMicroelectronics
1: €9.43
4,097In Stock

Mfr. Part No.
STM32L4A6VGT6

Mouser Part No
511-STM32L4A6VGT6

STMicroelectronics

ARM Microcontrollers - MCU Ultra-low-power FPU Arm Cortex-M4 MCU 80 MHz 1 Mbyte of Flash USB OTG, LCD, AES-

Learn More

Datasheet

4,097In Stock

€9.43

€6.90

€6.39

€6.06

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-100

ARM Cortex M4

32 bit

80 MHz

1 MB

320 kB

3 x 12 bit

136 I/O

- 40 C

+ 85 C

Tray

8-bit Microcontrollers - MCU Ultra LP 8-Bit MCU 64kB Flash 16MHz EE

STM8L052R8T6
STMicroelectronics
1: €1.54
36,071In Stock

Mfr. Part No.
STM8L052R8T6

Mouser Part No
511-STM8L052R8T6

STMicroelectronics

8-bit Microcontrollers - MCU Ultra LP 8-Bit MCU 64kB Flash 16MHz EE

Learn More

Datasheet

36,071In Stock

€1.54

€1.14

€1.03

€0.894

View

Min.: 1
Mult.: 1

8-bit Microcontrollers - MCU

SMD/SMT

LQFP-64

STM8

8 bit

16 MHz

64 kB

4 kB

12 bit

54 I/O

- 40 C

+ 85 C

Tray

8-bit Microcontrollers - MCU 8-bit Ultralow MCU 16 KB Flash

STM8L151K4T6
STMicroelectronics
1: €2.16
24,372In Stock

Mfr. Part No.
STM8L151K4T6

Mouser Part No
511-STM8L151K4T6

STMicroelectronics

8-bit Microcontrollers - MCU 8-bit Ultralow MCU 16 KB Flash

Learn More

Datasheet

24,372In Stock

€2.16

€1.61

€1.47

€1.32

View

Min.: 1
Mult.: 1

8-bit Microcontrollers - MCU

SMD/SMT

LQFP-32

STM8

8 bit

16 MHz

16 kB

2 kB

12 bit

30 I/O

- 40 C

+ 85 C

Tray

8-bit Microcontrollers - MCU 8-bit MCU Value Line 16 MHz 8kb FL 128EE

STM8S003F3P6
STMicroelectronics
1: €0.602
127,610In Stock

Mfr. Part No.
STM8S003F3P6

Mouser Part No
511-STM8S003F3P6

STMicroelectronics

8-bit Microcontrollers - MCU 8-bit MCU Value Line 16 MHz 8kb FL 128EE

Learn More

Datasheet

127,610In Stock

€0.602

€0.344

€0.324

€0.309

View

Min.: 1
Mult.: 1

8-bit Microcontrollers - MCU

SMD/SMT

TSSOP-20

STM8

8 bit

16 MHz

8 kB

1 kB

10 bit

16 I/O

- 40 C

+ 85 C

Tube

ARM Microcontrollers - MCU 32-Bit ARM Cortex M0 64 Kbytes 2.0 - 3.6V

STM32F051R8T6
STMicroelectronics
1: €4.91
20,848In Stock

Mfr. Part No.
STM32F051R8T6

Mouser Part No
511-STM32F051R8T6

STMicroelectronics

ARM Microcontrollers - MCU 32-Bit ARM Cortex M0 64 Kbytes 2.0 - 3.6V

Learn More

Datasheet

20,848In Stock

€4.91

€3.38

€3.15

€2.77

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-64

ARM Cortex M0

32 bit

48 MHz

64 kB

8 kB

12 bit

55 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU Mainstream Arm Cortex-M0 Access line MCU 128 Kbytes of Flash 48 MHz CPU & CEC fu

STM32F071RBT6TR
STMicroelectronics
1: €5.68
5,526In Stock

Mfr. Part No.
STM32F071RBT6TR

Mouser Part No
511-STM32F071RBT6TR

STMicroelectronics

ARM Microcontrollers - MCU Mainstream Arm Cortex-M0 Access line MCU 128 Kbytes of Flash 48 MHz CPU & CEC fu

Learn More

Datasheet

5,526In Stock

Cut Tape

€5.68

€3.90

€3.64

€3.20

Reel

€2.29

View

MouseReel Available

Min.: 1
Mult.: 1

Reel: 1,000

ARM Microcontrollers - MCU

SMD/SMT

LQFP-64

ARM Cortex M0

32 bit

48 MHz

128 kB

16 kB

12 bit

51 I/O

- 40 C

+ 85 C

Reel, Cut Tape, MouseReel

ARM Microcontrollers - MCU 32BIT CORTEX M3 64PINS 128KB

STM32F100RBT6B
STMicroelectronics
1: €6.65
4,913In Stock

Mfr. Part No.
STM32F100RBT6B

Mouser Part No
511-STM32F100RBT6B

STMicroelectronics

ARM Microcontrollers - MCU 32BIT CORTEX M3 64PINS 128KB

Learn More

Datasheet

4,913In Stock

€6.65

€4.88

€4.55

€4.00

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-64

ARM Cortex M3

32 bit

24 MHz

128 kB

8 kB

12 bit

51 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU ARM 32Bit Value Line 64-Pin 32kB Flash

STM32F100RCT6B
STMicroelectronics
1: €7.52
3,773In Stock

Mfr. Part No.
STM32F100RCT6B

Mouser Part No
511-STM32F100RCT6B

STMicroelectronics

ARM Microcontrollers - MCU ARM 32Bit Value Line 64-Pin 32kB Flash

Learn More

Datasheet

3,773In Stock

€7.52

€5.25

€5.01

€4.35

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-64

ARM Cortex M3

32 bit

24 MHz

256 kB

24 kB

12 bit

51 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU ARM 32Bit Value Line 100-Pin 32kB Flash

STM32F100VCT6BTR
STMicroelectronics
1: €7.60
3,422In Stock

Mfr. Part No.
STM32F100VCT6BTR

Mouser Part No
511-STM32F100VCT6BTR

STMicroelectronics

ARM Microcontrollers - MCU ARM 32Bit Value Line 100-Pin 32kB Flash

Learn More

Datasheet

3,422In Stock

Cut Tape

€7.60

€5.70

€5.44

€4.72

View

Reel

€3.62

MouseReel Available

Min.: 1
Mult.: 1

Reel: 1,000

ARM Microcontrollers - MCU

SMD/SMT

LQFP-100

ARM Cortex M3

32 bit

24 MHz

256 kB

24 kB

12 bit

80 I/O

- 40 C

+ 85 C

Reel, Cut Tape, MouseReel

ARM Microcontrollers - MCU 32BIT Cortex M3 64KB 20KB RAM 2X12 ADC

STM32F103R8T6
STMicroelectronics
1: €7.10
16,996In Stock

Mfr. Part No.
STM32F103R8T6

Mouser Part No
511-STM32F103R8T6

STMicroelectronics

ARM Microcontrollers - MCU 32BIT Cortex M3 64KB 20KB RAM 2X12 ADC

Learn More

Datasheet

16,996In Stock

€7.10

€4.96

€4.73

€4.11

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-64

ARM Cortex M3

32 bit

72 MHz

64 kB

20 kB

12 bit

64 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU 32BIT Cortex M3 128K 20KB RAM 2X12 ADC

STM32F103VBT6
STMicroelectronics
1: €8.50
5,659In Stock

Mfr. Part No.
STM32F103VBT6

Mouser Part No
511-STM32F103VBT6

STMicroelectronics

ARM Microcontrollers - MCU 32BIT Cortex M3 128K 20KB RAM 2X12 ADC

Learn More

Datasheet

5,659In Stock

€8.50

€6.37

€6.07

€5.27

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-100

ARM Cortex M3

32 bit

72 MHz

128 kB

20 kB

12 bit

100 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU 32BIT Cortex M3 256kB Flash 100pin

STM32F103VCT6
STMicroelectronics
1: €9.46
13,389In Stock

Mfr. Part No.
STM32F103VCT6

Mouser Part No
511-STM32F103VCT6

STMicroelectronics

ARM Microcontrollers - MCU 32BIT Cortex M3 256kB Flash 100pin

Learn More

Datasheet

13,389In Stock

€9.46

€7.31

€6.97

€6.05

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-100

ARM Cortex M3

32 bit

72 MHz

256 kB

48 kB

12 bit

80 I/O

- 40 C

+ 85 C

Tray

ARM Microcontrollers - MCU 32-Bit Cortex 64Kb Performance Line

STM32F103VCT6TR
STMicroelectronics
1: €9.46
36,415In Stock

Mfr. Part No.
STM32F103VCT6TR

Mouser Part No
511-STM32F103VCT6TR

STMicroelectronics

ARM Microcontrollers - MCU 32-Bit Cortex 64Kb Performance Line

Learn More

Datasheet

36,415In Stock

Cut Tape

€9.46

€7.31

€6.97

€6.05

View

Reel

€4.54

MouseReel Available

Min.: 1
Mult.: 1

Reel: 1,000

ARM Microcontrollers - MCU

SMD/SMT

LQFP-100

ARM Cortex M3

32 bit

72 MHz

256 kB

48 kB

12 bit

80 I/O

- 40 C

+ 85 C

Reel, Cut Tape, MouseReel

ARM Microcontrollers - MCU 32BIT Cortex M3 Performance LINE

STM32F103ZET6
STMicroelectronics
1: €12.25
3,999In Stock

Mfr. Part No.
STM32F103ZET6

Mouser Part No
511-STM32F103ZET6

STMicroelectronics

ARM Microcontrollers - MCU 32BIT Cortex M3 Performance LINE

Learn More

Datasheet

3,999In Stock

€12.25

€9.31

€8.92

€7.86

View

Min.: 1
Mult.: 1

ARM Microcontrollers - MCU

SMD/SMT

LQFP-144

ARM Cortex M3

32 bit

72 MHz

512 kB

64 kB

12 bit

112 I/O

- 40 C

+ 85 C

Tray

STMicroelectronics Embedded Processors & Controllers

Types of Embedded Processors & Controllers

Customer Service Office

Company

Resources

Support

BGA-100
BGA-132
BGA-144
BGA-168
BGA-169
BGA-176
BGA-216
BGA-292
BGA-64
BGA-73
CSP-100
CSP-115
CSP-36
CSP-48
CSP-64
CSP-72
CSP-81
FPBGA-292
FPBGA-302
FPBGA-386

ARM1176JZ-F
ARM Cortex-A35
ARM Cortex A35, ARM Cortex M33
ARM Cortex A7
ARM Cortex A7, ARM Cortex M4
ARM Cortex M0
ARM Cortex-M0, ARM Cortex-M4
ARM Cortex M0+
ARM Cortex M0+, ARM Cortex M4
ARM Cortex M3
ARM Cortex M33
Arm Cortex-M33
ARM Cortex M33, ARM Cortex A35
ARM Cortex M35P
ARM Cortex M4
ARM Cortex M4, ARM Cortex M0+
ARM Cortex M4, ARM Cortex M7
ARM Cortex M4F
ARM Cortex M55
ARM Cortex M7

8 MHz
15 MHz
16 MHz
16 MHz/32 MHz
20 MHz
24 MHz
32 MHz
36 MHz
48 MHz
56 MHz
64 MHz
64 MHz, 32 MHz
72 MHz
80 MHz
80 MHz, 120 MHz
80 MHz, 160 MHz
84 MHz
96 MHz
100 MHz
110 MHz

0 B
1 KB
2 kB
4 kB
8 kB
16 kB
32 kB
64 KB
64 kB
96 kB
128 KB
128 kB
160 kB
176 kB
192 kB
256 KB
256 kB
320 kB
384 kB
512 kB

384 B
512 B
1 kB
1.5 kB
2 kB
4 kB
6 kB
8 kB
10 kB
12 kB
16 KB
16 kB
18 kB
20 kB
22 kB
24 kB
32 KB
32 kB
36 kB
40 kB

2 x 10 bit
2 x 10 bit, 5 x 12 bit, 6 x 16 bit
2 x 12 bit
2 x 16 bit
2 x 6 bit/8 bit/10 bit/12 bit
2 x 8 bit/10 bit/12 bit
3 x 10 bit, 5 x 12 bit, 6 x 16 bit
3 x 12 bit
3 x 12 bit, 1 x 16 bit
3 x 16 bit
4 x 12 bit
4 x 6 bit/8 bit/10 bit/12 bit
5 x 12 bit
5 x 12 bit, 2 x 16 bit
6 bit/8 bit/10 bit/12 bit
8 bit to 16 bit
10 bit
10 bit, 12 bit
10 bit, 3 x 12 bit
10 bit, 4 x 12 bit

5 I/O
6 I/O
8 I/O
9 I/O
10 I/O
11 I/O
14 I/O
15 I/O
16 I/O
17 I/O
18 I/O
19 I/O
20 I/O
21 I/O
22 I/O
23 I/O
24 I/O
25 I/O
26 I/O
27 I/O