ENV - Set Environment

Memory Size Enable [Y/N] = Y?

YMemory will be sized for Self Test diagnostics. (Default)

NMemory will not be sized for Self Test diagnostics.

Memory Size Starting Address = 00000000?

The default Starting Address is $00000000.

Memory Size Ending Address = 02000000?

The default Ending Address is the calculated size of local memory. If the memory start is changed from $00000000, this value will also need to be adjusted.

DRAM Speed in NANO Seconds = 60?

The default setting for this parameter will vary depending on the speed of the DRAM memory parts installed on the board. The default is set to the slowest speed found on the available banks of DRAM memory.

ROM First Access Length (0 - 31) = 10?

This is the value programmed into the MPC105 “ROMFAL” field (Memory Control Configuration Register 8: bits 23-27) to indicate the number of clock cycles used in accessing the ROM. The lowest allowable ROMFAL setting is $00; the highest allowable is $1F. The value to enter depends on processor speed; refer to your specific processor and memory mezzanine module user’s manual for appropriate values. The default values vary according to the system’s bus clock speed.

Note ROM First Access Length is not applicable to the MCPN750. The configured value is ignored by PPCBug.

ROM Next Access Length (0 - 15) = 0?

The value programmed into the MPC105 “ROMNAL” field (Memory Control Configuration Register 8: bits 28-31) to represent wait states in access time for nibble (or burst) mode ROM accesses. The lowest

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Motorola IH5, MCPN750A manual Default Starting Address is $00000000