GS2101M IP2WiFi Adapter Command Reference Guide
1VV0301499
Rev. 2.0
27
2019-08-05
2.5.1 Unsolicited/Unassociated/Beacon Mode Data Handling
In
Unsolicited Data Mode
(data transmission without association), data transfer is
managed using
escape sequences
. Each escape sequence starts with the ASCII character 27
(0x1B), equivalent to the Escape <ESC> key. For more details, see
5.2.1 Unassociated/Unsolicited Tx, page 90
)
2.5.2 Software Flow Control
The
Software Flow Control
(for UART interface) works only with ASCII data transfers
and cannot be used for binary data. For SPI interface and use of flow control (see
Interface and Configuration, page 37
)
If software flow control is enabled, and the interface receives an XOFF character from the
serial host, it stops sending to the host until it receives an XON character. If the GS node is
receiving data over the wireless connection and the host/mcu sends XOFF character to the
GS node to indicate its inability to process the incoming data over UART Interface, then
there is a possibility for the receiving wireless buffers to be full on the GS node side and
the GS node might drop the data.
If software flow control is enabled, then the interface sends an XOFF character to the host
when it will be unable to service the serial port. The XON character is sent when the
interface is once again able to accept data over the serial port.
2.5.3 Hardware Flow Control
The Hardware Flow Control is a handshake mechanism between the Serial host and
IP2WiFi Application on UART interface, using two additional CTS and RTS connections.
This feature prevents the UART hardware FIFO overflow on IP2WiFi Application due to
high speed data transmission from/to the IP2WiFi Application. If hardware flow control is
enabled, an RTS/CTS handshake will occur between the serial host and the GS node. This
is a hardware feature and available only for UART interface.
The IP2WiFi Application uses both CTS and RTS signals as “low” to indicate the readiness
to send or receive data from serial host.
NOTE:
With initialization, the GS node treats the serial channel as clear with no
restrictions on data transmission or reception; no explicit XON by the GS node or
required from the Host, even if flow control is enabled.
