Nxp Semiconductors UM10237 用户手册
UM10237_2
© NXP B.V. 2008. All rights reserved.
User manual
Rev. 02 — 19 December 2008
605 of 792
NXP Semiconductors
UM10237
Chapter 22: LPC24XX I
2
C interfaces I
2
C0/1/2
4. Set up Master Transmit mode data buffer.
5. Set up Master Receive mode data buffer.
6. Initialize Master data counter.
7. Exit
10.7 Master Transmitter states
10.7.1 State : 0x18
Previous state was State 8 or State 10, Slave Address + Write has been transmitted, ACK
has been received. The first data byte will be transmitted, an ACK bit will be received.
has been received. The first data byte will be transmitted, an ACK bit will be received.
1. Load I2DAT with first data byte from Master Transmit buffer.
2. Write 0x04 to I2CONSET to set the AA bit.
3. Write 0x08 to I2CONCLR to clear the SI flag.
4. Increment Master Transmit buffer pointer.
5. Exit
10.7.2 State : 0x20
Slave Address + Write has been transmitted, NOT ACK has been received. A Stop
condition will be transmitted.
condition will be transmitted.
1. Write 0x14 to I2CONSET to set the STO and AA bits.
2. Write 0x08 to I2CONCLR to clear the SI flag.
3. Exit
10.7.3 State : 0x28
Data has been transmitted, ACK has been received. If the transmitted data was the last
data byte then transmit a Stop condition, otherwise transmit the next data byte.
data byte then transmit a Stop condition, otherwise transmit the next data byte.
1. Decrement the Master data counter, skip to step 5 if not the last data byte.
2. Write 0x14 to I2CONSET to set the STO and AA bits.
3. Write 0x08 to I2CONCLR to clear the SI flag.
4. Exit
5. Load I2DAT with next data byte from Master Transmit buffer.
6. Write 0x04 to I2CONSET to set the AA bit.
7. Write 0x08 to I2CONCLR to clear the SI flag.
8. Increment Master Transmit buffer pointer
9. Exit
10.7.4 State : 0x30
Data has been transmitted, NOT ACK received. A Stop condition will be transmitted.
1. Write 0x14 to I2CONSET to set the STO and AA bits.
2. Write 0x08 to I2CONCLR to clear the SI flag.
3. Exit