TOOLSTICK540DC Silicon Laboratories Inc, TOOLSTICK540DC Datasheet - Page 137

• Manufacturer Part Number: TOOLSTICK540DC
• Description: DAUGHTER CARD TOOLSTICK F540
• Manufacturer: Silicon Laboratories Inc
• Series: ToolStickr
• Type: MCUr

Specifications of TOOLSTICK540DC

• Contents: Daughter Card
• Processor To Be Evaluated: C8051F54x
• Processor Series: C8051F54x
• Interface Type: USB
• Operating Supply Voltage: 2.7 V to 3.6 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: C8051F54x
• For Use With: 336-1345 - TOOLSTICK BASE ADAPTER336-1182 - ADAPTER USB DEBUG FOR C8051FXXX
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1717

17.2. Programmable Internal Oscillator
All C8051F54x devices include a programmable internal high-frequency oscillator that defaults as the sys-
tem clock after a system reset. The internal oscillator period can be adjusted via the OSCICRS and OSCI-
FIN registers defined in SFR Definition 17.3 and SFR Definition 17.4. On C8051F54x devices, OSCICRS
and OSCIFIN are factory calibrated to obtain a 24 MHz base frequency. Note that the system clock may be
derived from the programmed internal oscillator divided by 1, 2, 4, 8, 16, 32, 64, or 128, as defined by the
IFCN bits in register OSCICN. The divide value defaults to 128 following a reset.
17.2.1. Internal Oscillator Suspend Mode
When software writes a logic 1 to SUSPEND (OSCICN.5), the internal oscillator is suspended. If the sys-
tem clock is derived from the internal oscillator, the input clock to the peripheral or CIP-51 will be stopped
until one of the following events occur:





When one of the oscillator awakening events occur, the internal oscillator, CIP-51, and affected peripherals
resume normal operation, regardless of whether the event also causes an interrupt. The CPU resumes
execution at the instruction following the write to SUSPEND.
Note: When entering suspend mode, firmware must set the ZTCEN bit in REF0CN (SFR Definition 7.1).
Port 0 Match Event.
Port 1 Match Event.
Port 2 Match Event.
Port 3 Match Event.
Comparator 0 enabled and output is logic 0.
Rev. 1.1
C8051F54x
137