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chip-specific docs

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Tom Nisbet 2023-09-19 12:17:07 -04:00
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@ -61,7 +61,8 @@ chips, allowing a 32KB chip to be programmed in just a few seconds.
## PromDeviceSST39SF
The SST39SF0x0 NOR Flash chips use fixed 4KB sectors that must be manually erased before a
SST39SF0x0 NOR Flash chips are 5V-only chips that use a command register for program and
erase operations. They use fixed 4K-byte sectors that must be manually erased before a
new program operation, but the code manages this transparently. Whenever a write is
started to a new segment, the driver first initiates an erase of that sector. A second
write to the same sector will not cause an erase, so it is possible to write to a segment
@ -69,14 +70,15 @@ multiple times with no additional steps as long as the writes are to different p
the sector. For example, 256 bytes could be written to the start of a sector from one
file and then 512 bytes could be written to the end of the sector from another file.
Writing data that spans multiple sectors also works with no additional steps. When
a sector boundary is crossed, the new sector is erased and set as the current sector.
Writing data that spans multiple sectors also works with no additional steps. When a
sector boundary is crossed, the new sector is erased and set as the current sector.
The SST39SF driver supports a manual erase from the command line using the E command.
This is only needed if data will be rewritten to the same location after a previous write
to that sector.
The SST39SF driver supports a manual erase from the command line using the E command. This
is only needed if data will be rewritten to the same location after a previous write to
that sector.
All programming and erase operations for the 39SF chips require only a single 5V power supply.
All programming and erase operations for the 39SF chips require only a single 5V power
supply.
## PromDeviceSST28SF
@ -237,11 +239,15 @@ pulsing _WE_.
|Model |Manufacturer |Type |Module |Notes|
|:--- |:--- |:--- |:--- |:--- |
|M27C4001 |ST Micro |EEPROM | |VCC=6.5V, VPP=12.75V to pgm|
|M27C2001 |ST Micro |EPROM | |VCC=6.5V, VPP=12.75V to pgm|
|M27C4001 |ST Micro |EPROM | |VCC=6.5V, VPP=12.75V to pgm|
|W27C512 |Winbond |EEPROM |27 |Continual 12V or 14V for program/erase,VPP on OE|
|AM28F512 |AMD |EEPROM | ||
|AM29F040 |AMD |EEPROM | ||
|AMS29AF010|AMS | | ||
|AMS29AF010| | | ||
|2764 |SEEQ |EPROM | ||
|W29C040 |Winbond | | ||
# Chip Manufacturers