C8051F581-IMR Silicon Labs, C8051F581-IMR Datasheet - Page 143

• Manufacturer Part Number: C8051F581-IMR
• Description: 8-bit Microcontrollers - MCU 50MIPS 128kB 8kB SPI
• Manufacturer: Silicon Labs

Specifications of C8051F581-IMR

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

15.4.3. System Clock
1. If operating from an external crystal, be advised that crystal performance is susceptible to electrical
2. If operating from the external oscillator, switch to the internal oscillator during Flash write or erase
Additional Flash recommendations and example code can be found in ”AN201: Writing to Flash from Firm-
ware" available from the Silicon Laboratories web site.
SFR Definition 15.1. PSCTL: Program Store R/W Control
SFR Address = 0x8F; SFR Page = 0x00
Name
Reset
Bit
7:2
Type
1
0
Bit
interference and is sensitive to layout and to changes in temperature. If the system is operating in an
electrically noisy environment, use the internal oscillator or use an external CMOS clock.
operations. The external oscillator can continue to run, and the CPU can switch back to the external
oscillator after the Flash operation has completed.
Unused
PSWE
Name
PSEE
R
7
0
Read = 000000b, Write = don’t care.
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 location 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.
Program Store Write Enable.
Setting this bit allows writing a byte of data to the Flash program memory using the
MOVX write 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 write instruction targets Flash
memory.
R
6
0
R
5
0
Rev. 1.2
R
4
0
Function
R
3
0
C8051F58x/F59x
R
2
0
PSEE
R/W
1
0
PSWE
R/W
0
0
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