DS87000

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Edit

This command provides full screen edit capability of the programmer’s encryption vector. All bytes of the

vector are displayed on the screen, and each can be individually edited. The vector is presented in hex format

in the center of the screen, and the ASCII representation is to the right. If the hex value cannot be represented

in printable ASCII, a period (.) is displayed. The cursor may be placed over either the hex or ASCII value and

a new value entered. When exiting the edit function after modifying one or more bytes of the vector, the user

will be asked if the changes are to be saved. If yes, the new vector will be stored in the programmer.

The user may clear the entire encryption vector by entering an ALT-C. Note that a cleared encryption vector

is all ones, and if a cleared vector is stored in the device, there will be no encryption. A series of random

numbers will be used to fill the encryption vector if an ALT-R is entered. A randomly selected encryption

vector provides a more secure device.

DEVICE MENU

Blank Check

This command reads the device to confirm that it is completely erased (all 1’s). The user is prompted to enter

the beginning and ending address of the range to be checked. The default range is displayed, and may be

modified or accepted as is.

Read

This command will read all or part of the device's EPROM and store it in the programmer's buffer memory.

The user is prompted to enter the beginning and ending address of the range to be read. The default range is

displayed, and may be modified or accepted as is.

If an encryption vector has been stored in the device, the data will be encrypted as it is read. If the intent is to

read non-encrypted data, the read must be performed before the encryption array is written to the device. The

lock bits also have an effect on this function. If either of the two highest levels of lock are written to the

device, the data read will be all ones.

Verify

Verify that the device's EPROM contains the same information as the programmer's buffer. The user is

prompted to enter the beginning and ending address of the range to be verified. The default range is

displayed, and may be modified or accepted as is.

Since the verify function actually reads data from the device, verify must be performed before the device’s

encryption array, lock bits, and/or serial number are written. After the encryption array is written to the

device, all data that is read will be encrypted as a standard function of this security measure. After the lock

bits are written, it may not be possible to read the device at all, depending on the level of lock. The serial

number is unique for every device programmed, so it will not verify from one device to another.

IBlank Check

This command reads the device to confirm that it can be programmed with the contents of the buffer. This

mode makes use of the fact that a completely blank device is not required for proper programming. For

instance, if the device contains a 0 bit where a 0 bit is to be programmed, then it does not matter that the bit

is not "blank" (i.e., 1). Also, if a byte already contains the byte to be programmed, then it does not need to be

re-programmed, and it does not matter that it is not blank. The user is prompted to enter the beginning and