PC87109VBE Nuvoton Technology Corporation of America, PC87109VBE Datasheet - Page 35

• Manufacturer Part Number: PC87109VBE
• Description: IC CONTROLLER ADV UART 32-LQFP
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of PC87109VBE

• Features: Transmit Deferral
• Number Of Channels: 2, DUART
• Fifo's: 16 Byte
• Voltage - Supply: 5V
• With Irda Encoder/decoder: Yes
• With False Start Bit Detection: Yes
• With Modem Control: Yes
• Mounting Type: Surface Mount
• Package / Case: 32-LQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: *PC87109VBE

3.6.3.1 FRM_ST - Frame Status Byte at ST_FIFO Bottom, Read Only
This register returns the status byte at the bottom of the ST_FIFO. If the LOST_FR bit is 0, bits 0 to 4 indicate if any error
condition occurred during reception of the corresponding frame. Error conditions will also affect the error flags in the LSR
register.
3.6.3.2 RFRL(L)/LSTFRC - Received Frame Length /Lost-Frame-Count at ST_FIFO Bottom,
Read Only
This register should be read only when the VLD bit in FRM_ST is 1. The information returned depends on the setting of the
LOST_FR bit. Upon reset, all bits are set to 0.
LOST_FR = 0 => Least significant 8 bits of the received frame length.
LOST_FR = 1 => Number of lost frames
3.6.3.3 RFRL(H) - Received-Frame-Length at ST_FIFO Bottom, Read Only
This register should be read only when the VLD bit in FRM_ST is 1. The information returned depends on the setting of the
LOST_FR bit. Upon reset, all bits are set to 0.
LOST_FR = 0 => Most significant 5 bits of the received frame length.
LOST_FR = 1 => All 0's
Reading this register removes the bottom ST_FIFO entry.
Bits
Function
Reset State
B0
B1
B2
B3
B4
B5
B6
B7
OVR2 - Overrun Error 2.
This bit is set to 1 when incoming characters or entire frames have been discarded due to the ST_FIFO being full.
OVR1 - Overrun Error 1.
This bit is set to 1 when incoming characters or entire frames have been discarded due to the RX_FIFO being full.
BAD_CRC - CRC Error.
Set to 1 when a mismatch between the received CRC and the receiver-generated CRC is detected.
PHY_ERR - Physical Layer Error.
Set to 1 when an encoding error or the sequence BOF-data-BOF is detected in FIR mode or an abort condition is
detected in MIR mode.
MAX_LEN - Maximum Frame Length Exceeded.
Set to 1 when a frame exceeding the maximum length has been received.
Reserved.
Returned data is indeterminate.
LOST_FR - Lost Frame Indicator Flag.
Indicates the type of information provided by this ST_FIFO entry.
0 => Entry provides status information and length for a received frame.
1 => Entry provides overrun indications and number of lost frames.
VLD - ST_FIFO Entry Valid.
When set to 1, the bottom ST_FIFO entry contains valid data.
VLD
B7
0
LOST_FR
B6
0
Figure 3-18. Frame Status Byte
Res
B5
0
MAX_LEN
35
B4
0
PHY_ERR
B3
0
BAD_CRC
B2
0
OVR1
B1
0
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OVR2
B0
0