Bus

bus.command.read_timeout

Abbreviation

bu c t

Access

get/set

Description

Controls the maximum amount of time that the read command waits to complete a read.

The amount of data to be read is specified in the parameters of the read command.

Note : a timeout still returns success.

Arguments

<timeout ms> where:

• <timeout ms> - timeout duration specified in milliseconds. Range: 0 - 65535

Default

100

Properties

• takes effect immediately

Gecko OS Kernel Plugin

• kernel

Get example

> get bu c t
R000005
100

Set example

> set bu c t 256
R000008
Set OK

bus.command.rx_bufsize

Abbreviation

bu c r

Access

get/set

Description

Configure the size of the UART rx buffer in command mode.

Note : in stream mode if bus.stream.flush_count > 0 then the UART RX buffer size is set to:

buffer size = MAX(bus.stream.flush_count, bus.command.rx_bufsize)

This greatly helps data throughput in flushed stream mode. See bus.stream.flush_count .

Arguments

<buffer size>

Range 256 to 10000 bytes

Default

4096 (bytes)

Properties

• save and reboot to apply change

Gecko OS Kernel Plugin

• kernel

Get example

> get bu c r
R000006
4096

Set example

> set bu c r 512
R000008
Set OK

bus.command.write_check_enabled

Abbreviation

bu c c

Access

get/set

Description

This bus.command.write_check_enabled variable determines whether the write buffer is checked when the stream_write is executed.

This allows writing data to a network stream with the certainty that, if the write fails, no data was read or sent.

If bus.command.write_check_enabled = 1 the check takes place. The check ensures that there is enough room to hold all of the read data. The check takes place before data is read from the data bus. If the write buffer does not have enough room to hold the requested read amount after bus.command.write_timeout milliseconds, the stream_write command fails with an error code: 9 = Bounds error . See Serial Interface, Response Format .

If the stream_write command fails with error code 9 = Bounds error , then no data issued in the stream_write command was read or sent.

To query how much data is available in the write buffer , issue the poll -t command to return the amount of room available in the write buffer .

The write buffer is dependent on the stream type and only available for network connections.

For network connections using a TCP socket, the write buffer is the minimum of:

• TCP TX window - the amount of buffer the remote TCP connection advertises it can receive
• Network TX buffer - The TX portion of the buffer specified by network.buffer.size and network.buffer.rxtx_ratio

The following streams use a TCP socket:

• TCP server/client
• TLS server/client
• Websocket server/client

A UDP client/server stream write buffer is dependent only on the TX portion of the network buffer.

The following example shows how the variable is used.

Assume a TCP stream 0 is opened, and issuing the poll 0 -t command returns:

poll 0 -t
0,3345

This indicates the write command can accept no more than 3345 bytes without waiting for more buffer space from the remote side.

If bus.command.write_check_enabled = 1 , the check takes place, and issuing write 0 6000 fails after bus.command.write_timeout milliseconds if the remote TCP connection does not update its TCP window:

write 0 6000
<6000 bytes of data>
R900014
Bounds error

In this case, none of the 6000 bytes of data was read from the bus and thus none of the data was sent.

Note : If bus.command.write_check_enabled = 0 then the behavior is as in previous releases: Gecko OS immediately reads the data bus and attempts to write the data within bus.command.write_timeout milliseconds. If the write times out then the amount of data actually sent to the remote side is unknown. An error code of 1 = Command Failed is returned if the write times out.

See also:

• stream_write
• stream_poll
• bus.command.write_timeout

Arguments

<1|true|on/0|false|off> where

• 0 or false or off : write buffer checking does NOT take place
• 1 or true or on : write buffer checking takes place

Default

0

Properties

• takes effect immediately

Gecko OS Kernel Plugin

• kernel

Get example

> get bu c c

Set example

> set bu c c 1
Set OK

bus.command.write_timeout

Abbreviation

bu c w

Access

get/set

Description

Controls the maximum amount of time the write command blocks waiting for more data to be read from the data bus.

Note : On timeout the command fails.

Arguments

<timeout ms> where:

• <timeout ms> - timeout duration specified in milliseconds. Range: 0 - 65535 ms

Default

25000

Properties

• takes effect immediately

Gecko OS Kernel Plugin

• kernel

Get example

> get bu c w
R000007
25000

Set example

> set bu c w 60000
R000008
Set OK

bus.data_bus

Abbreviation

bu d

Access

get/set

Description

The serial data bus to use for communication with a host.

Arguments

<uart0/uart1>

Default

<platform dependent>

Properties

• save and reboot to apply change
• available in Safe Mode
• preserved by NVM Backup
• lockable: see system.variable_lock

Gecko OS Kernel Plugin

• kernel

Get example

> get bu d
R000007
uart1

Set example

> set bu d uart0
R000008
Set OK

bus.log_bus

Abbreviation

bu l

Access

get/set

Description

All log messages are sent to this serial bus regardless of bus mode.

Arguments

<uart0/uart1>

Default

<platform dependent>

Properties

• save and reboot to apply change
• available in Safe Mode
• preserved by NVM Backup
• lockable: see system.variable_lock

Gecko OS Kernel Plugin

• kernel

Get example

> get bu l
R000007
uart1

Set example

> set bu l uart0
R000008
Set OK

bus.mode

Abbreviation

bu m

Access

get/set

Description

The serial bus mode.

Arguments

<command/stream>

Default

command

Properties

• save and reboot to apply change
• available in Safe Mode
• preserved by NVM Backup
• lockable: see system.variable_lock

Gecko OS Kernel Plugin

• kernel

Get example

> get bu m
R000009
command

Set example

> set bu m command
R000008
Set OK

bus.stream.cmd_gpio

Abbreviation

bu s g

Access

get/set

Description

The GPIO used to force the module into command mode (from stream mode). A value of -1 disables this feature.

Arguments

<[GPIO#]/[-1]>

where:

• -1 means no GPIO is assigned and feature is disabled

Default

-1

Properties

• save and reboot to apply change

Gecko OS Kernel Plugin

• bus.mode.stream

Get example

> get bu s g
R000003
0

Set example

> set bu s g 6
R000008
Set OK

bus.stream.cmd_seq

Abbreviation

bu s s

Access

get/set

Description

Break-in sequence for stream mode. After 3 seconds of inactivity on the serial interface, sending the break-in sequence changes stream mode to command mode; send 'exit' to return to stream mode.

Note : The length of the break-in sequence affects the allowed minimum value of bus.stream.flush_count .

This feature may be disabled with the following command:

set bus.stream.cmd_seq ""

When disabled, the break-in sequence is disabled. This allows for binary data streams or for any streams which may be interpreted incorrectly as the break-in sequence.

Note : If this feature is disabled it's strongly recommended to enable bus.stream.cmd_gpio and/or another remote command feature, such as the remote terminal or the Gecko OS Web App .

Otherwise the Gecko OS command console will be inaccessible until the module is factory reset.

Arguments

<1-15 characters>

Default

$$$

Properties

• save and reboot to apply change

Gecko OS Kernel Plugin

• bus.mode.stream

Get example

> get bu s s
R000005
$$$

Set example

> set bu s s ###
R000008
Set OK

bus.stream.flush_count

Abbreviation

bu s c

Access

get/set

Description

Number of bytes received on the serial bus before flushing to the network stream.

In stream mode , if the value of bus.stream.flush_count is greater than bus.command.rx_bufsize , the buffer size is set to the bus.stream.flush_count value. See bus.command.rx_bufsize .

Arguments

<count> where <count> can range from minimum value to maximum value :

• minimum value : MAX(16, len(bus.stream.cmd_seq)*2)
  i.e. the minimum value is the maximum of 16 and 2 x the length of the bus.stream.cmd_seq variable
  For example, if bus.stream.cmd_seq is the default $$$ , its length is 3, so minimum value is the maximum of 16 and 2*3 = 16.
• maximum value : 1460

Default

1460

Properties

• save and reboot to apply change

Gecko OS Kernel Plugin

• bus.mode.stream

Get example

> get bu s c
R000006
1460

Set example

> set bu s c 1450
R000008
Set OK

bus.stream.flush_time

Abbreviation

bu s t

Access

get/set

Description

Timeout in milliseconds before bytes are automatically flushed to the network stream.

If set to 0, automatic flush is disabled.

To achieve optimal throughput, set flush time to 0. Gecko OS transfers data with 'Zero Copy'. i.e. a data packet is directly transferred from the bus to network or network to bus.

Arguments

<0-65535>

Default

50

Properties

• save and reboot to apply change

Gecko OS Kernel Plugin

• bus.mode.stream

Get example

> get bu s t
R000004
20

Set example

> set bu s t 10
R000008
Set OK

bus.stream.flush_time_reset

Abbreviation

bu s r

Access

get/set

Description

Flag whether to reset the flush timer if data is received before the flush timeout expires. When this variable is set and data is streaming, data is flushed only when the buffer is full. This allows for efficient use of the packet buffer and prevents packet fragmentation. When the variable is reset, the buffer is flushed at intervals of bus.stream.flush_time and also when the buffer is full. This allows data to be sent at consistent intervals.

Arguments

<1|true|on/0|false|off>

Default

0

Properties

• save and reboot to apply change

Gecko OS Kernel Plugin

• bus.mode.stream

Get example

> get bus.stream.flush_time_reset
0

Set example

> set bus.stream.flush_time_reset 1
Set OK