MCP48FVB21 datasheet(52/84 Pages) MICROCHIP

52 / 84 page

MCP48FVBXX

DS20005466A-page 52

 2015 Microchip Technology Inc.

7.0.1

COMMAND BYTE

The Command Byte has three fields: the address, the

command, and one data bit (see Figure 7-1).

The device memory is accessed when the master

sends a proper command byte to select the desired

operation. The memory location getting accessed is

contained in the command byte’s AD4:AD0 bits. The

action desired is contained in the command byte’s

C1:C0 bits, see Table 7-3. C1:C0 determines if the

desired memory location will be read or written.

As the command byte is being loaded into the device

(on the SDI pin), the device’s SDO pin is driving. The

SDO pin will output high bits for the first seven bits of

that command. On the 8th bit, the SDO pin will output

the CMDERR bit state (see Section 7.0.3, “Error

Condition”

7.0.2

DATA BYTES

These commands concatenate the two data bytes

after the command byte, for a 24-bit long command

(see Figure 7-1).

FIGURE 7-1:

24-bit SPI Command Format.

TABLE 7-2:

COMMAND BITS OVERVIEW

C1:C0

bit

states

Command

# of Bits

Normal or HV

Write Data

24 Bits

Normal

Reserved

—

Reserved

—

Read Data

24 Bits

Normal

Memory

24-bit Command

Data Bits (8, 10, or 12 bits)

Address

Command

Bits

= Write Data

= Reserved

= Read Data

C C

1 0

Command

Bits

Command Byte

Data Word (2 Bytes)

(1)

Note 1:

This command uses the 24-bit format.

(1)

MCP48FVB21 Fiches technique(PDF) 52 Page - Microchip Technology

MCP48FVB21 Fiches technique(HTML) 52 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

Fiches technique Télécharger

Lien URL