Z8F640x/Z8F480x/Z8F320x/Z8F240x/Z8F160x
Z8 Encore!®
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4. The I2C Controller loads the I2C Shift register with the contents of the I2C Data
register.
5. After the first bit has been shifted out, a Transmit interrupt is asserted.
6. Software responds by writing eight bits of address to the I2C Data register.
7. The I2C Controller completes shifting of the two address bits and a 0 (write).
8. The I2C slave sends an acknowledge by pulling the SDA signal Low during the next
high period of SCL.
9. The I2C Controller loads the I2C Shift register with the contents of the I2C Data
register.
10. The I2C Controller shifts out the next eight bits of address. After the first bits are
shifted, the I2C Controller generates a Transmit interrupt.
11. Software responds by setting the STARTbit of the I2C Control register to generate a
repeated START.
12. Software responds by writing 11110Bfollowed by the 2-bit slave address and a 1
(read).
13. Software responds by setting the NAK bit of the I2C Control register, so that a Not
Acknowledge is sent after the first byte of data has been read. If you want to read only
one byte, software responds by setting the NAK bit of the I2C Control register.
14. After the I2C Controller shifts out the address bits mentioned in step 9, the I2C slave
sends an acknowledge by pulling the SDA signal Low during the next high period of
SCL.
15. The I2C Controller sends the repeated START condition.
16. The I2C Controller loads the I2C Shift register with the contents of the I2C Data
register.
17. The I2C Controller sends 11110Bfollowed by the 2-bit slave read and a 1 (read).
18. The I2C slave sends an acknowledge by pulling the SDA signal Low during the next
high period of SCL.
19. The I2C slave sends a byte of data.
20. A Receive interrupt is generated.
21. Software responds by reading the I2C Data register.
22. Software responds by setting the STOPbit of the I2C Control register.
23. A NAK condition is sent to the I2C slave.
24. A STOP condition is sent to the I2C slave.
PS017609-0803
I2C Controller
ZILOG [ ZILOG, INC. ]
