MICROWIRE.
MICROWIRE National Semiconductor SPI 0 (CPOL = 0, CPHA = 0).
3- Maxim
, DQ.
QSPI
, SPI, .
, SPI , .. JTAG Flash-, .. SD MMC.
. 1. SPI
MOSI | DO, SDO, DOUT | MOSI | DI, SDI, DIN | ||
MISO | DI, SDI, DIN | MISO | DO, SDO, DOUT | ||
SCLK | DCLOCK, CLK, SCK | SCLK | DCLOCK, CLK, SCK | ||
SS | CS | ( ) | SS | CS | ( ) |
. 2. SPI
SPI | ||||
CPOL | ||||
CPHA | ||||
I2C.
1 I2C
Philips, . I2C ( Inter-Integrated Circuit), . I2C , (SCL) , (SDA) . , +5 1...10 , . 2- , 100 /.
"Master" "Slave". "Master" (SCL) , , . "Slave"- . "Slave"- "" , , . , "MultiMaster"-, "Master"-, "Slave"-, "Master"-, , "Slave", "Master"-. "MultiMaster" . , ( ) , , .
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SCL SDA . 1 ( ). ( 1) SDA SCL. SDA SCL. "Slave"- "" SCL , , , "Master"- SCL, .
1 I2C
I2C "START" "STOP", ( 2). SDA SCL, . "START"- SDA, SCL , , "STOP"- SDA SCL.
2 "START" / "STOP" I2C
SCL, . (8 ) 9 SCL. - (ACK) , "" . , , "Master", "Slave" , , ACK, .
, "Master" "START"-, "Slave"- ( 3), ( 1...7) "R/W" ( 0), , 0 "Master" "Slave" ( 3), 1 "Slave" ( 3). I2C -, 7- , 0-. ( , R/W), SCL "Master"-.
"Master" ACK, , ACK, (. 3).
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"Slave"- , "START"- "STOP"- ( 3).
3 /
, I2C, . -, , , . , . , "Slave" 1010. Philips.
"" . , "START", . , , ( ) . "Slave"-. IBM PC .
, , , . . , . . ( ), ( ). , , , , .
, , , , , .
"STOP", . 10 . , .
. .
. , "Slave" , , , , . SCL, . , . "STOP".
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(. 3). , . , "START", "Slave" . .
, , , , , ( ).
I2C , . I2C, , Philips, I2C. , (EEPROM) 24 8- , . : DS1307 DS3231, PCF8574, 4- 8- PCF8591.
I2C- : "Master"- "Slave"- . , SCL "Master"- , "Master"- , SCL. , "Slave"- , . () "Slave"- I2C. Philips PCF80C552 (652), Microchip PIC16F88 (PIC16F690, PIC18F2620 .), Motorola MC68HC705CJ4 (BD3, E5).
"Master"- . 0 . 1 SCL SDA. MCS-51 , , (Motorola 68HCxx, Microchip PIC, Atmel AVR) . , "Microchip. Embedded Control Handbook 1994/1995" PIC c EEPROM 24Cxx, . , EEPROM , 100% , . , SCL ( "Slave"-, ), , , .
" " () ( , , , I2C SCL SDA , ) , . 0, . PIC "TRISx", , "PORTx". AVR MC68HC05 (08, 11), "DDRx" "PORTx", , PIC . 0 "TRISx" . 0 , AVR MC68HC05 . 1 "DDRx" . 0 .
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. , I2C () ( I2C- , ), . , , .
, , "START" "STOP"-, , . , (AVR, PIC). , , SDA SCL SCL (2,4 100 /). , "Slave"- , .
SCL "Slave"-. "Master"- SCL , , SCL -.