C8051F320DK Silicon Laboratories Inc, C8051F320DK Datasheet - Page 100

• Manufacturer Part Number: C8051F320DK
• Description: DEV KIT FOR C8051F320/F321
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051F320DK

• Contents: Evaluation Board, Power Supply, USB Cables, Adapter and Documentation
• Processor To Be Evaluated: C8051F320/F321
• Interface Type: USB
• Silicon Manufacturer: Silicon Labs
• Core Architecture: 8051
• Silicon Core Number: C8051F320
• Silicon Family Name: C8051F32x
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: Silicon Laboratories C8051F320, C8051F321
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1260

C8051F320/1
10.1. Power-On Reset
During power-up, the device is held in a reset state and the /RST pin is driven low until VDD settles above
V
typically less than 0.3 ms. Figure 10.2. plots the power-on and VDD monitor reset timing.
On exit from a power-on reset, the PORSF flag (RSTSRC.1) is set by hardware to logic 1. When PORSF is
set, all of the other reset flags in the RSTSRC Register are indeterminate (PORSF is cleared by all other
resets). Since all resets cause program execution to begin at the same location (0x0000) software can
read the PORSF flag to determine if a power-up was the cause of reset. The content of internal data mem-
ory should be assumed to be undefined after a power-on reset. The VDD monitor is enabled following a
power-on reset.
Software can force a power-on reset by writing ‘1’ to the PINRSF bit in register RSTSRC.
100
RST
. A Power-On Reset delay (T
Logic HIGH
Figure 10.2. Power-On and VDD Monitor Reset Timing
Logic LOW
2.70
2.4
2.0
1.0
/RST
V
PORDelay
RST
Power-On
Reset
) occurs before the device is released from reset; this delay is
T
PORDelay
Rev. 1.4
Monitor
Reset
VDD
VDD
t