Crate jtag_scanner 

JTAG boundary scanning module.

WARNING: This tool may damage your hardware in EXTEST mode, especially when the target is not a development board: to reduce the risk, do not enable the output of any pin with unknown functionality for a long time (the duration should be as short as possible).

Usage

Building the PinScanner

• Check for compatible debug adapters, connect the adapter to the target, connect the adapter to the PC and power on the target;
• With the backend-jtag-taps feature of jtag-scanner enabled, construct and configure a Cable instance;
• Create a PinScannerBuilder with the Cable instance, and (optionally) check the result of get_id_codes to make sure the TAP chain is working;
• With the builder, call scan_tap_info with a directory path for scanning BSDL files, then call build to build the PinScanner.

Using the PinScanner

• Enumerate in tap_infos to get the index of the TAP that you want to control.
• Get PinId values via get_pin_id, providing the port name as the argument; or iterate through pin_ids_for_tap.
• Set the TAP to SAMPLE or EXTEST mode by set_tap_state.
• Call get_pin_state or set_pin_state, and then update or write_update.
• Check PinScanner::batch if higher transmission efficiency is required.

Creating bitbang IO interface adapters

Some adapters (e.g. I2C, NOR and NAND flash) may be added in the future. These adapters should depend on PinGroup instead of using PinScanner directly; they are all under protocols feature gate.

Modules

protocols

IO interface adapters. All of them are under the protocol feature gate.

Structs

BsrEdit

Write-only BSR buffer. Used in the batch operation API.

BsrView

Read-only BSR buffer. Used in the batch operation API.

Error

The error type used in this crate.

PinGroup

Groups pins and assign given names to each pin, restricting the usage of PinScanner within the group. Implements PinGroup.

PinGroupItem

Items required during construction of PinGroup.

PinId

Unique pin identifier associated with a PinScanner instance. This is not intended to be persistent or serializable.

PinIdIter

Iterates through all PinIds for a TAP in the chain handled by PinScanner.

PinScanner

Basic structure for doing boundary scanning. Expects a fixed chain of devices.

PinScannerBuilder

The only way to build PinScanner; detects IDCODEs of devices on the chain, and scan for BSDL files.

PinState

Lastly captured states of scan cells of a pin.

Enums

ErrorKind

A list of general categories of errors produced in this crate.

TapInfo

Needed information for each TAP on the chain.

TapState

Supported TAP states for normal operations.

Traits

Backend

Trait for supported JTAG adapter drivers (currently all of them are from jtag-taps).