Using Arm Virtual Hardware Targets

This section describes how to use the Arm Virtual Hardware (AVH) Targets.

The AVH simulation models are based on the Arm Fast Models Fixed Virtual Platforms with extensions for Virtual Peripherals. The table below shows the available models:

AVH Simulation Models	Processor Core	Overview Description
VHT_MPS2_Cortex-M0	Cortex-M0	ARM Cortex-M0 SMM on V2M-MPS2 (AppNote AN382)
VHT_MPS2_Cortex-M0plus	Cortex-M0+	ARM Cortex-M0+ SMM on V2M-MPS2 (AppNote AN383)
VHT_MPS2_Cortex-M3	Cortex-M3	ARM Cortex-M3 SMM on V2M-MPS2 (AppNote AN385)
VHT_MPS2_Cortex-M4	Cortex-M4	ARM Cortex-M4 SMM on V2M-MPS2 (AppNote AN386)
VHT_MPS2_Cortex-M7	Cortex-M7	ARM Cortex-M7 SMM on V2M-MPS2 (AppNote AN399)
VHT_MPS2_Cortex-M23	Cortex-M23	ARM Cortex-M23 IoT Subsystem for V2M-MPS2+ (AppNote AN519)
VHT_MPS2_Cortex-M33	Cortex-M33	ARM Cortex-M33 IoT Subsystem for V2M-MPS2+ (AppNote AN505)
VHT_MPS3_Corstone_SSE-300	Cortex-M55	Corstone-300 FVP Technical Overview (PDF), Memory map overview
VHT_Corstone_SSE-300_Ethos-U55	Cortex-M55, Ethos-U55	Corstone-300 FVP Technical Overview (PDF), Memory map overview
VHT_Corstone_SSE-300_Ethos-U65	Cortex-M55, Ethos-U65	Corstone-300 FVP Technical Overview (PDF), Memory map overview
VHT_Corstone_SSE-310	Cortex-M85, Ethos-U55	Corstone-310 FVP Technical Overview (PDF), Memory map overview
VHT_Corstone_SSE-310_Ethos-U65	Cortex-M85, Ethos-U65	Corstone-310 FVP Technical Overview (PDF), Memory map overview

Additionally following simulation models are provided without support of Virtual Peripherals:

Simulation Model	Processor Core	Overview Description
FVP_Corstone-1000	Cortex-A35, Cortex-M0+, Cortex-M3	Arm Corstone-1000 for MPS3 (AppNote AN550)

Execution

Simulation models can be executed in Linux environment by using their model names, for example VHT_Corestone_SSE-300_Ethos-U55, and on Windows platform the models are provided as executables files, for example VHT_Corestone_SSE-300_Ethos-U55.exe. See Usage Examples.

Command Line Options

The command line options can be listed using the -help command. For example in Linux environment:

VHT_Corstone_SSE-300_Ethos-U55 -help

The AVH simulation models can be configured using the option -f FILE that specifies a config-file. The available config-file options can be listed with the option -l.

Usage Examples

Below is an example of running a program on the AVH model for Corstone-300 with Ethos-U55 in Linux environment:

VHT_Corstone_SSE-300_Ethos-U55 -V "..\VSI\audio\python" -f vht_config.txt -a Objects\microspeech.axf --stat --simlimit 24

Where:

• -V specifies that path to the Python scripts for Virtual Peripherals.
• -f specifies the config-file for the AVH simulation model.
• -a specifies the application to load.
• –stat instructs to print run statistics on simulation exit.
• –simlimit specifies the maximum number of seconds to simulate.

The content of the vht_config.txt could be:

# Parameters:
# instance.parameter=value       #(type, mode) default = 'def value' : description : [min..max]
#------------------------------------------------------------------------------
core_clk.mul=32000000                                 # (int   , init-time) default = '0x17d7840' : Clock Rate Multiplier. This parameter is not exposed via CADI and can only be set in LISA
mps3_board.telnetterminal0.start_telnet=0             # (bool  , init-time) default = '1'      : Start telnet if nothing connected
mps3_board.uart0.out_file=-                           # (string, init-time) default = ''       : Output file to hold data written by the UART (use '-' to send all output to stdout)
mps3_board.visualisation.disable-visualisation=1      # (bool  , init-time) default = '0'      : Enable/disable visualisation
#------------------------------------------------------------------------------

Where:

• core_clk.mul=32000000 specifies the virtual time, in this case 32MHz CPU clock.
• mps3_board.telnetterminal0.start_telnet=0 disables the Telnet connectivity.
• mps3_board.uart0.out_file=- UART output is send to stdout.
• mps3_board.visualisation.disable-visualisation=1 disables the graphical user interface of the AVH.

Execution stop

Embedded applications typically run with an infinite loop that ensures continuous program execution. But for executing regression tests as part of Continuous Integration (CI) workflows it is often required that program execution is stopped after a test is completed, so that the next test can be started.

AVH simulation models provide shutdown_on_eot parameter that enables simple implementation of such program exit. The parameter should be set in the model configuration file (vht_config.txt explained above), for example for VHT_Corstone_SSE-300:

mps3_board.uart0.shutdown_on_eot=1   # (bool, init-time) default = '0' : Shutdown simulation when a EOT (ASCII 4) char is transmitted (useful for regression tests when semihosting is not available)

And then to trigger the shutdown, a EOT (ASCII 4) symbol can be transmitted to the corresponding serial interface from the program. The code below demonstrates an example, where the execution is stopped after target execution count is achieved. In this implementation the STDIO is assumed to be retargeted to the UART0:

while (1)  {
  printf ("Hello World %d\r\n", count);
  if (count > 100) printf ("\x04");  // EOT (0x04) stops simulation
  count++;
  osDelay (1000);
}