PEP Modular Computers 15311, User Manual

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VMEM-F1 Chapter 2 Functional Description
July 30, 1997 Page 2- 9 © PEP Modular Computers
2.4.1 Serial EEPROM Control Register
Address: Jumper selected A16 base a HEX 3
Format: Byte
Access: Read and write
Value after Reset: HEX 00
Register Description:
2.5 Default FLASH Enable
Default FLASH Enable is jumper selectable (J5). If selected, the VMEM-F1 responds to the A24 ad-
dress without being initialized. The default base address is 00 00 00 HEX in address space. The default
page is 0. The Default FLASH Enable function may be useful if the FLASH contains a CPU startup
code.
Notes
The board can be initialized at any time to a different base address and AM codes, regardless of whether
Default FLASH Enable is selected.
The jumper position for the Default FLASH Enable can be read back via the board status register. The
green front panel LED displays the board enabled status if selected by default or after the base address
register of the board has been initialized.
EEP_DAT Serial Data (SDI or SDO), VMEM-F1 and VMEM-F1-PB1
EEP_CLK Serial Clock (SCK), VMEM-F1 and VMEM-F1-PB1
EEP_CS0 Chip Select (CS), VMEM-F1
EEP_CS1 Chip Select (CS), VMEM-F1-PB1
EEP_CS1
EEP_CS0
0 1 2 3 4 5 6 7
Reserved
Reserved
EEP_CLK EEP_DAT Reserved
Reserved