MBM29PL64LM datasheet(28/69 Pages) SPANSION

28 / 69 page

MBM29PL64LM90/10

Extended Sector Group Protection

In addition to normal sector group protection, the device has Extended Sector Group Protection as extended

function. This function enables protection of the sector group by forcing VID on RESET pin and writes a command

sequence. Unlike conventional procedures, it is not necessary to force VID and control timing for control pins.

The only RESET pin requires VID for sector group protection in this mode. The extended sector group protection

requires VID on RESET pin. With this condition, the operation is initiated by writing the set-up command (60h)

into the command register. Then the sector group addresses pins (A21, A20, A19, A18, A17, A16 and A15) and (A6,

A3, A2, A1, A0) = (0, 0, 0, 1, 0) should be set to the sector group to be protected (set VIL for the other addresses

pins is recommended), and write extended sector group protection command (60h). A sector group is typically

protected in 250

µs. To verify programming of the protection circuitry, the sector group addresses pins (A21, A20,

A19, A18, A17, A16 and A15) and (A6, A3, A2, A1, A0) = (0, 0, 0, 1, 0) should be set and write a command (40h).

Following the command write, a logical “1” at device output DQ0 will produce for protected sector in the read

operation. If the output data is logical “0”, write the extended sector group protection command (60h) again. To

terminate the operation, set RESET pin to VIH. (Refer to the “Extended Sector Group Protection Timing Diagram”

in sTIMING DIAGRAM and “Extended Sector Group Protection Algorithm” in sFLOW CHART.)

Query Command (CFI : Common Flash Memory Interface)

The CFI (Common Flash Memory Interface) specification outlines device and host system software interrogation

handshake which allows specific vendor-specified software algorithms to be used for entire families of devices.

This allows device-independent, JEDEC ID-independent, and forward-and backward-compatible software sup-

port for the specified flash device families. Refer to CFI specification in detail.

The operation is initiated by writing the query command (98h) into the command register. Following the command

write, a read cycle from specific address retrieves device information. Please note that output data of upper byte

(DQ15 to DQ8) is “0”. Refer to the CFI code table. To terminate operation, it is necessary to write the Reset

command sequence into the register. (See “Common Flash Memory Interface Code” in sDEVICE BUS OPER-

ATION.)

HiddenROM Mode

(1) HiddenROM Region

The HiddenROM (HiddenROM) feature provides a Flash memory region that the system may access through

a new command sequence. This is primarily intended for customers who wish to use an Electronic Serial Number

(ESN) in the device with the ESN protected against modification. Once the HiddenROM region is protected, any

further modification of that region is impossible. This ensures the security of the ESN once the product is shipped

to the field.

The HiddenROM region is 256 bytes / 128 words in length. After the system writes the HiddenROM Entry

command sequence, it may read the HiddenROM region by using device addresses A6 to A0 (A21 to A15 are all

“0”). That is, the device sends only program command that would normally be sent to the address to the

HiddenROM region. This mode of operation continues until the system issues the Exit HiddenROM command

sequence, or until power is removed from the device. On power-up, or following a hardware reset, the device

reverts to sending commands to the address.

If you request Fujitsu to program the ESN in the device, please contact a Fujitsu representative for more infor-

mation.

MBM29PL64LM датащи(PDF) 28 Page - SPANSION

MBM29PL64LM датащи(HTML) 28 Page - SPANSION

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69

датащи скачать

ссылки URL