MCP16502 datasheet(71/86 Pages) MICROCHIP

71 / 86 page

 2019-2022 Microchip Technology Inc. and its subsidiaries

DS20006275D-page 71

MCP16502

4.8.3.4

Block Read (Auto-Increment Mode)

This command reads a block of bytes, starting from a

designated register that is specified through the com-

mand byte. The address gets incremented by one

automatically and the registers are read in order starting

from the address provided by the command byte.

The Block/Auto-Increment Read command is as

follows, whereas the timing diagram is illustrated in

Figure 4-15.

Send Start sequence.

Send 7-bit target address.

Send the R/W bit = 0 to indicate a Write operation.

Wait for Acknowledge from the target.

Send the command byte – initial address that

needs to be read.

Wait for Acknowledge from the target.

Send Start sequence again (Repeated Start, Sr).

Send the 7-bit target address.

Send R/W bit = 1 to indicate a Read operation.

10. Wait for Acknowledge from the target.

11. Receive the 8-bit data from the Target register

indicated in Step 5, starting from the MSB.

12. Acknowledge from the host receiver.

13. Receive the 8-bit data from the next register,

starting from the MSB.

14. Acknowledge from the host receiver.

15. Repeat Steps 13 and 14 until the last byte.

16. Stop sequence is sent.

In Block Read, the register order will be automatically

incremented by one step, regardless of the register

order. So, for example, after reading from register loca-

tion 0x15, the next register address to be read will be

0x16, not 0x20.

Reading from non-existent or not accessible register

addresses will stream out 0xFF.

Also note that if the host keeps reading data beyond the

last register location, the MCP16502 streams out 0xFF

(all ‘1‘s). There is no register address wrap-around.

In Block Read Auto-Increment mode, the host receiver

must signal an end-of-data to the transmitter by not

generating an Acknowledge on the last byte that has

been clocked out of the target. In this event, the trans-

mitter must leave the data line as high to enable the

host to generate a Stop condition.

FIGURE 4-15:

I2C Block Read.

4.8.3.5

I2C Interface Disable

While not necessarily contained in a well-designed

implementation, the MCP16502 also supports I2C

interface disabling.

This is achieved by issuing three separated single

Write commands as follows (ADDRESS equals the

device address in 7-bit format, default = 0x5B):

ADDRESS = 0x5B, COMMAND = 0xEA,

DATA = 0xBD

ADDRESS = 0x5B, COMMAND = 0xE9,

DATA = 0xBD

ADDRESS = 0x5B, COMMAND = 0xEC,

DATA = 0xBD

Upon an ACK of the last byte, the I2C interface will no

longer respond to the device address or any other bus

transaction.

To enable the I2C interface again, power (SVIN) must

be cycled.

Note:

On the last byte, the host receiver issues

a NACK in place of an ACK to signal the

end of the data transfer.

SDA

Start Condition

ACK from

Address

Command Byte

ACK from

(Repeated)

Start Condition

R/W

ACK from

Address

Data from Register X+n

Stop Condition

DATA (first byte)

R/W

At this moment,

-Transmitter becomes

-Receiver

and

Receiver becomes

Transmitter

(cont.)

** *

(cont.)

** *

(cont.)

** *

Data from Register X

DATA (first byte)

Data from Register X+1

DATA (first byte)

MCP16502 Datasheet(PDF) 71 Page - Microchip Technology

MCP16502 Datasheet(HTML) 71 Page - Microchip Technology

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

Datasheet Download

Link URL