Core Devices

CPU

A CHARON-AXP emulated CPU is configured with the "ace_mode" parameter.

Two HP Alpha CPU implementations are available: the standard HP Alpha instruction decoder and the optional high performance Advanced CPU Emulation mode ("ACE"). The ACE option optimizes the HP Alpha instruction interpretation and significantly improves performance. It also requires approximately twice the amount of host memory to store the optimized code.

ACE optimization is performed dynamically during execution. It does not need to write optimized code back to disk, ACE provides its full capability instantly. The optimization does not compromise the HP Alpha instruction decoding; CHARON-AXP remains fully HP Alpha hardware compatible and completely transparent to the HP Alpha operating systems and applications.

Both CPU implementations passed the HP HP Alpha Architecture (AXE) tests, the standard qualification for HP Alpha instruction execution correctness.

The default HP Alpha CPU mode is determined by the specific CHARON-AXP product license.

Parameter	Type	Values
ace_mode	Boolean	true or false.

This statement enables the ACE mode if the CHARON-AXP license permits it. If this statement is omitted from the CHARON-AXP configuration file and the license permits it, "true" is the default, otherwise "false" is the default. For test purposes the ACE mechanism can be disabled with:

set cpu ace_mode=false

"set cpu ace_mode=true" is ignored when the license does not permit ACE operation.

The CHARON-AXP log file displays the status of the ACE option.

The ACE mode is disabled when the host system does not meet the minimum physical requirements for this operation. If the emulator appears to not run at its normal performance, check the log file for a change in the ACE mode and verify that sufficient host resources, especially memory, are available.

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RAM

The CHARON-AXP memory subsystem is permanently loaded and has the logical name "ram".

Parameter	Type	Description
size	Numeric	Size of the emulated memory in MB.

Example:

set ram size = 512

The amount of memory is capped at a maximum, this is defined in the CHARON license key. If the host system cannot allocate enough memory to map the requested emulated memory, CHARON-AXP generates an error message in the log file and reduces its effective memory size.

The following table lists the values of emulated RAM for various hardware models of virtual HP Alpha systems:

Hardware Model	RAM size (in MB)
	Min	Max	Default	Increment
PDP1193	2	4	2	2
PDP1194	2	4	2	2
MicroHP Alpha_II	1	16	16	1,8,16
MicroHP Alpha_3600	16	64	16	16
MicroHP Alpha_3900	16	64	16	16
HP Alphaserver_3600	16	64	16	16
HP Alphaserver_3900	16	64	16	16
HP Alphaserver_3600_128	32	128	32	32
HP Alphaserver_3900_128	32	128	32	32
MicroHP Alpha_3100_Model_96	16	128	16	16
HP Alphastation_4000_Model_90	16	128	16	16
HP Alpha_4000_Model_106	16	128	16	16
HP Alpha_6000_Model_310	32	512	32	32
HP Alphaserver_3600_512	32	512	32	32
HP Alphaserver_3900_512	32	512	32	32
MicroHP Alpha_3100_Model_98	16	512	16	16
HP Alpha_4000_Model_108	16	512	16	16
HP Alpha_4000_Model_700	64	512	64	64
HP Alpha_4000_Model_705	64	512	64	64
HP Alpha_6610	128	3584	128	128
HP Alpha_6620	128	3584	128	128
HP Alpha_6630	128	3584	128	128
HP Alpha_6640	128	3584	128	128
HP Alpha_6650	128	3584	128	128
HP Alpha_6660	128	3584	128	128

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TOY

CHARON-AXP maintains its time and date using the "toy" (time-of-year) component. In order to preserve the time and date while a virtual system is not running, the TOY component uses a binary file on the host system to store the date and time relevant data. The name of the file is specified by the “container” option of the "toy" component.

Parameter

Type

Description

container

Text string

Specifies a name for the file in which CHARON-AXP preserves the time and date during its “offline” period. This file also keeps some console parameters (such as the default boot device).

By default it is left unspecified.

it is recommended to specify the full path to the TOY file.

Example:

set toy container="C:\Charon\my_virtual_system.dat"

The CHARON-AXP time zone may be different from that of the host system. Correct CHARON time relies on the correctness of the host system time to calculate the duration of any CHARON “offline” periods. (i.e. while the virtual system is not running). Every time CHARON comes on line it calculates a Delta time (the system time is used if there is no TOY file). Therefore, if the host system time is changed while CHARON is not running, the CHARON time may be incorrect when CHARON is restarted and the CHARON time must be set manually.

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KW11-L and KW11-P Timers (PDP-11)

The KW11-L timer is used in PDP-11 system emulation. It supports a 50Hz, 60Hz and 70Hz frequency.

A time correction mechanism handles any time slips between the emulated and the host system time. The KW11-L frequency can be set in the configuration file as follows:

set kw11 frequency=50

For PDP-11 configurations this device is loaded automatically.

The KW11-P is a programmable timer for PDP-11 systems. The hardware KW11-P timer runs on a 100KHz clock and can be programmed to interrupt at any frequency up to 100KHz.

The software KW11-P implementation is limited to 1KHz due to the host operating system limitations; it can be programmed to interrupt at any frequency up to 1KHz.

The current implementation does not contain a way to handle a time slip recovery from the host system time. This can lead to time skew between the emulated and host system time when the programmed frequencies are not divisors of 1000.

The KW11-P is loaded automatically. It does not have any configuration file parameters because it is set by the PDP-11 software.

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ROM

The System Flash ROM file conserves specific parameters between reboots.

Parameter

Type

Description

container

Text string

Specifies the name of a file in which CHARON-AXP stores an intermediate state of its Flash ROM. This state includes, for example, most of the console parameters.

By default it is left unspecified.

it is recommended to specify the full path to this file

Example:

set rom container=”C:\Charon\my_virtual_system.rom”

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PDP-11 Boot ROM

PDP-11 Boot ROM has two parameters: ‘ext_rom’ and ‘ext_rom_address’. Specify the external ROM file and offset within the file to load the ROM from. This feature allows changing the used boot ROM to a custom one.

Parameter	Type	Description
ext_rom	Text string	Specifies a file containing external boot code
ext_rom_address	Numeric	Specifies an offset to be used for the file specified by the ext_rom parameter

Example:

set rom ext_rom=”custom_rom.bin”
set rom ext_rom_address=0

The ROM file must contain a binary dump.

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EEPROM

Parameter Type Value

container

Text string

A string specifying a file name to store the content of the EEPROM.

Example:

set eeprom container="vx6k610.rom"

This command enables EEPROM parameters (e.g., default boot drive) to be automatically saved to a specified file. The EEPROM file is created in the directory in which CHARON-AXP starts. The EEPROM file is created or overwritten each time any parameter relevant to the EEPROM content is changed.

it is recommended to specify the full path to this file

Example:

set eeprom container=”C:\Charon\my_virtual_system.rom”

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Auto Boot

CHARON-AXP systems can be configured to boot the operating system automatically at start up.

MicroHP Alpha3100, HP Alphastation 4000, HP Alpha6310 and HP Alpha 4000

Those models boot automatically if the correct boot flags are set (and saved in the HP Alpha console files) using the following command:

Console Parameter Description

halt

Determines whether the MicroHP Alpha3100, HP Alphastation 4000, HP Alpha6310 and HP Alpha 4000 boot automatically if the correct boot flags are set (and saved in the HP Alpha console files).

The value is:

"reboot"

Example:

>>>set halt reboot

Please check that the "toy container" and "rom container" parameters are specified in the configuration file to store the boot flags.

MicroHP Alpha II, MicroHP Alpha 3600/3900 and HP Alphaserver 3600/3900

The ROM of the MicroHP Alpha II, MicroHP Alpha 3600, MicroHP Alpha 3900, HP Alphaserver 3600 and HP Alphaserver 3900 servers does not allow the HP Alpha console to accept the command setting "auto-boot". Instead, an automatic boot on startup can be specified in the CHARON-AXP configuration file as follows:

Parameters Type Value

bdr boot

Text string

Determines whether the MicroHP Alpha II, MicroHP Alpha 3600, MicroHP Alpha 3900, HP Alphaserver 3600 and HP Alphaserver 3900 servers boot automatically if the correct boot flags are set (and saved in the HP Alpha console files).The value is:

"auto"

Example:

set bdr boot=auto

Check that the "toy container" and "rom container" parameters are specified in the configuration file to store the boot flags.

PDP11/93 and PDP11/94

The ROM of the PDP11/93 and PDP11/94 does not allow the PDP11 console to accept the command setting "auto-boot". Instead, automatic boot on startup can be specified in the CHARON-PDP configuration file as follows:

Parameters Type Value

cpu_0 auto_boot

Text string

Determines whether the PDP11/93 or PDP11/94 server boots automatically from the specified disk.The value is the disk drive to boot from.

Example:

set cpu_0 auto_boot = "DU0"

Check that the "toy container" and "rom container" parameters are specified in the configuration file to store the boot flags.

HP Alpha66x0

Parameter Type Value

xmi boot

Text string

Determines whether the CHARON HP Alpha66x0 startup procedure stops at the ">>>" prompt after self-tests.The values are:

"auto"
"manual" (default)

Example:

set xmi boot = "auto"

The value "auto" enables automatic boot from a default boot specification, previously configured in the HP Alpha console.The value "manual" disables the automatic boot once the self tests are passed.

Check that the "toy container" and "rom container" parameters are specified in the configuration file to store the boot flags.

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