jtag sequence - 2022.2 English

Syntax

jtag sequence 

Create JTAG sequence object.

sequence state new-state [count]

Move JTAG state machine to <new-state> and then generate <count> JTAG clocks. If <clock> is given and <new-state> is not a looping state (RESET, IDLE, IRSHIFT, IRPAUSE, DRSHIFT or DRPAUSE), the state machine will move towards RESET state.

sequence irshift [options] [bits [data]] sequence drshift [options] bits [data]

Shift data in IRSHIFT or DRSHIFT state. Data is either given as the last argument or if -tdi option is given then data will be all zeros or all ones depending on the argument given to -tdi. The <bits> and <data> arguments are not used for irshift when the -register option is specified. Available options:

-register <name>

Select instruction register by name. This option is only supported for irshift.

-tdi <value>

TDI value to use for all clocks in SHIFT state.

-binary

Format of <data> is binary, for example data from a file or from binary format.

-integer

Format of <data> is an integer. The least significant bit of data is shifted first.

-bits

Format of <data> is a binary text string. The first bit in the string is shifted first.

-hex

Format of <data> is a hexadecimal text string. The least significant bit of the first byte in the string is shifted first.

-capture

Capture TDO data during shift and return from sequence run command.

-state <new-state>

State to enter after shift is complete. The default is RESET.

sequence delay usec

Generate delay between sequence commands. No JTAG clocks will be generated during the delay. The delay is guaranteed to be at least <usec> microseconds, but can be longer for cables that do not support delays without generating JTAG clocks.

sequence get_pin pin

Get value of <pin>. Supported pins are cable specific.

sequence set_pin pin value

Set value of <pin> to <value>. Supported pins are cable specific.

sequence atomic enable

Set or clear atomic sequences. This is useful to creating sequences that are guaranteed to run with precise timing or fail. Atomic sequences should be as short as possible to minimize the risk of failure.

sequence run [options]

Run JTAG operations in sequence for the currently selected jtag target. This command will return the result from shift commands using -capture option and from get_pin commands. Available options:

-binary

Format return value(s) as binary. The first bit shifted out is the least significant bit in the first byte returned.

-integer

Format return values(s) as integer. The first bit shifted out is the least significant bit of the integer.

-bits

Format return value(s) as binary text string. The first bit shifted out is the first character in the string.

-hex

Format return value(s) as hexadecimal text string. The first bit shifted out is the least significant bit of the first byte of the in the string.

-single

Combine all return values as a single piece of data. Without this option the return value is a list with one entry for every shift with -capture and every get_pin.

sequence clear

Remove all commands from sequence.

sequence delete

Delete sequence.

Returns

JTAG sequence object.

Examples

set seqname [jtag sequence]
$seqname state RESET
$seqname drshift -capture -tdi 0 256
set result [$seqname run]
$seqname delete