Datasheet

W5500 Datasheet Version1.0.9 55 / 66
3. After saving the transmitting data, update Sn_TX_WR to the
increased value as many as transmitting data size. If the increment value
exceeds the maximum value 0xFFFF(greater than 0x10000 and the carry
bit occurs), then the carry bit is ignored and will automatically update
with the lower 16bits value.
4. Transmit the saved data in Socket n TX Buffer by using SEND/SEND
command
Sn_RX_RSR (Socket n Received Size Register) [R] [0x0026-0x0027] [0x0000]
Sn_RX_RSR indicates the data size received and saved in Socket n RX Buffer. Sn_RX_RSR
does not exceed the Sn_RXBUF_SIZE and is calculated as the difference between
‘Socket n RX Write Pointer (Sn_RX_WR)’ and ‘Socket n RX Read Pointer (Sn_RX_RD)’.
Ex) In case of 2048(0x0800) in S0_RX_RSR,
0x0026
0x0027
0x08
0x00
Note) Because this register for representing the size information is 16 bits, it is
impossible to read all bytes at the same time. Before 16 bit-read operation is not
completed, the value may be changed.
Therefore, it is recommended that you read all 16-bits twice or more until getting
the same value.
Sn_RX_RD (Socket n RX Read Data Pointer Register) [R/W] [0x0028-0x0029] [0x0000]
Sn_RX_RD is initialized by OPEN command. Make sure to be read or updated as
follows.
1. Read the starting save address of the received data
2. Read data from the starting address of Socket n RX Buffer.
3. After reading the received data, Update Sn_RX_RD to the increased value as many
as the reading size. If the increment value exceeds the maximum value 0xFFFF,
that is, is greater than 0x10000 and the carry bit occurs, update with the lower
16bits value ignored the carry bit.
4. Order RECV command is for notifying the updated Sn_RX_RD to W5500.
Ex) In case of 2048(0x0800) in S0_RX_RD,
0x0028
0x0029
0x08
0x00
Sn_RX_WR (Socket n RX Write Pointer Register) [R] [0x002A-0x002B] [0x0000]