AS8218 datasheet(71/123 Pages) AMSCO

71 / 123 page

Data Sheet AS8218 / AS8228

Revision 3.0, 31-May-06

Page 71 of 123

BP1, BP0 allows the selection of one out of 4 protection schemes.

In order to protect against inadvertent programming the user can see these bits. Please note that the protected

range of EEPROM cannot be overwritten via an SCT command there anymore. Reprogramming must be done

with a dedicated program then.

Instruction Set

There must be at least 4 instructions with the coding shown in the table for they are deployed by the bootloader

to download the user program and by the SCT unit to upload the user program to the EEPROM.

Instruction

Name

Instruction

Format

Description

READ

03h

Read data from memory starting with selected address

WRITE

02h

Write data to memory beginning at selected address. Most EEPROMs allow page writing

of pages 16, 32, 64 or even more bytes for faster device programming. Before every

page write operation a WREN instruction must be applied – see also bootloading and

uploading sequence for details.

WREN

06h

Write enable EEPROM, enables write operation

RDSR

05h

Read EEPROM Status register, bit 0 = WIP required for AS8218 / AS8228

SPI Modes

These devices can be driven by a microcontroller with its SPI peripheral running in either of the two following

modes:

CPOL = 0, CPHA = 0

CPOL = 1, CPHA = 1 (It is recommended to set CPOL = 1, CPHA = 1 in your program: The build-in

bootloader uses this setting as well.)

For these two modes, input data is latched in on the rising edge of Serial Clock (SC), and output data is issued

on the falling edge of Serial Clock (SC).

The recommended mode is shown in Figure 12. The clock polarity SC is ‘1’ when the bus master is in Stand-by

mode and not transferring data (idle state):

SC remains at 1 for (CPOL = 1, CPHA = 1)

Figure 12: SPI modes recommended

EEP_SC(in)

EEP_SI(in)

EEP_SO(out

)

AS8218 датащи(PDF) 71 Page - ams AG

AS8218 датащи(HTML) 71 Page - ams AG

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 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

датащи скачать

ссылки URL