C8051F305-GSR Silicon Labs, C8051F305-GSR Datasheet - Page 92

• Manufacturer Part Number: C8051F305-GSR
• Description: 8-bit Microcontrollers - MCU 2KB 14Pin MCU
• Manufacturer: Silicon Labs

Specifications of C8051F305-GSR

• Rohs: yes
• Core: 8051
• Processor Series: C8051
• Data Bus Width: 8 bit

C8051F300/1/2/3/4/5
Accessing Flash from user firmware executing from an unlocked page:
Accessing Flash from user firmware executing from a locked page:
92
Bits7–2: UNUSED: Read = 000000b, Write = don’t care.
Bit1:
Bit0:
1. Any unlocked page except the page containing the Lock Byte may be read, written, or erased.
2. Locked pages cannot be read, written, or erased. An erase attempt on the page containing the
3. The page containing the Lock Byte cannot be erased. It may be read or written only if it is
4. Reading the contents of the Lock Byte is always permitted.
5. Locking additional pages (changing ‘1’s to ‘0’s in the Lock Byte) is not permitted.
6. Unlocking Flash pages (changing ‘0’s to ‘1’s in the Lock Byte) is not permitted.
7. The Reserved Area cannot be read, written, or erased. Any attempt to access the reserved area,
1. Any unlocked page except the page containing the Lock Byte may be read, written, or erased.
2. Any locked page except the page containing the Lock Byte may be read, written, or erased. An
3. The page containing the Lock Byte cannot be erased. It may only be read or written. An erase
4. Reading the contents of the Lock Byte is always permitted.
5. Locking additional pages (changing ‘1’s to ‘0’s in the Lock Byte) is not permitted.
6. Unlocking Flash pages (changing ‘0’s to ‘1’s in the Lock Byte) is not permitted.
7. The Reserved Area cannot be read, written, or erased. Any attempt to access the reserved area,
R/W
Bit7
—
Lock Byte will result in a Flash Error device reset.
unlocked. An erase attempt on the page containing the Lock Byte will result in a Flash Error device
reset.
or any other locked page, will result in a Flash Error device reset.
erase attempt on the page containing the Lock Byte will result in a Flash Error device reset.
attempt on the page containing the Lock Byte will result in a Flash Error device reset.
or any other locked page, will result in a Flash Error device reset.
PSEE: Program Store Erase Enable
Setting this bit (in combination with PSWE) allows an entire page of Flash program memory
to be erased. If this bit is logic 1 and Flash writes are enabled (PSWE is logic 1), a write to
Flash memory using the MOVX instruction will erase the entire page that contains the loca-
tion addressed by the MOVX instruction. The value of the data byte written does not matter.
0: Flash program memory erasure disabled.
1: Flash program memory erasure enabled.
PSWE: Program Store Write Enable
Setting this bit allows writing a byte of data to the Flash program memory using the MOVX
instruction. The Flash location should be erased before writing data.
0: Writes to Flash program memory disabled.
1: Writes to Flash program memory enabled; the MOVX instruction targets Flash memory.
SFR Definition 10.1.
R/W
Bit6
—
R/W
Bit5
—
R/W
Bit4
—
PSCTL: Program Store R/W Control
Rev. 2.9
R/W
Bit3
—
R/W
Bit2
—
PSEE
R/W
Bit1
PSWE
R/W
Bit0
SFR Address:
00000000
Reset Value
0x8F