AN93

Figure 75 illustrates the MCU software architecture, and the MCU and modem hardware connections.

(Optional)

Dot‐command shell

Application layer

modem_main.cdot_command_loop.c

Buffer management layer

status_control.c

application_buffers.c

test_code.c

Interrupt service and/or polling

ISR_and_polling.c

Hardware access layer

modem_hardware.c

MCU_hardware.c

MCU

Parallel interface

SPI master

MCU hardware

(UART, timers, etc.)

 

 

Parallel interface

SPI slave

UART interface

Modem

Hardware Interface

Transmit and

Register 1 (HIR1)

receive FIFOs

Figure 75. MCU Software and Modem Interface

Rev. 1.3

291

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Image 291
Silicon Laboratories SI2494/39, SI2493/57/34/15/04 manual Mcu