irscan

Scan the instruction registers of devices on the JTAG chain.

Syntax

irscan(device, instruction)

Where:

device	is an int4 that specifies the position of the device to access. Device positions are displayed by the devicelist command.
instruction	is the instruction to be scanned into the instruction register of the device. The instruction can be of any type except strings or arrays.

Description:

Use the irscan command with the drscan command to read from or write to the data register of a device on the target system boundary scan chain. The irscan command writes the designated instruction value into the instruction register of the specified device.

Example 1

To scan an instruction to device 4 on the JTAG chain:

Command Input:

irscan(4,5)

Example 2

To emulate idcode for device 0 on the JTAG chain:

Command input:

idcode(0)

Result:

182C1013

Command input:

define ord4 ReadArray[1]

irscan(0,2)

drscan(0, 0x20, ReadArray)

ReadArray[0]

Result:

182C1013

Related Topics

drscan

msgscan

tapdateset

tapdatashift