CSTCE12M0G55-R0 datasheet(15/26 Pages) MICROCHIP

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Installation and Operation

DS52056A-page 15

When GP8 is configured for its dedicated functionality, the pin can be used as a bus

release request for MCP2210 coming from another master. GP7 (configured for its

dedicated functionality) is used as an SPI bus release acknowledge signal towards the

requesting master. When an external SPI master requests the MCP2210 to release the

bus, the device completes the current SPI transfer (or it can be cancelled by the PC

application sending the proper USB command), then releases the bus and signals the

event on the acknowledge pin (GP7). The second master now has ownership of the

bus, and can keep it, as long as the SPI bus request pin (GP8) is kept asserted.

By using the dedicated functionality of the GP7 and GP8, the MCP2210 can be used

in a multiple SPI master system.

FIGURE 2-3:

MCP2210 TYPICAL USAGE DIAGRAM

MCP2210

SPI bus

Chip-Select lines

MOSI, MISO, SCK

USB

USB-to-SPI

bridge

SPI slave chip #1

SPI slave chip #n

External

Interrupt

(GP6)

Interrupt

...

SPI Master #2

SPI Bus Release Request

SPI Bus Release

Acknowledge

External

Interrupt

GP8

GP7

CSTCE12M0G55-R0 Folha de dados(PDF) 15 Page - Microchip Technology