JTAG Application
This application serves for the debugging of generic JTAG devices of all types, and the macros that it defines serve as the basis for other JTAG debugging applications, such as the one for the MSP430.
The pinout is standard for the MSP430 FET.
Clients
Please write one.
Development
Prior to any transaction, the SETUP (0x10) verb should be sent to the JTAG application to properly set the I/O pin directions. After that, the START (0x20) and STOP (0x21) verbs may be used to enter and exit the TAP.
The JTAG protocol itself is rather barren, defining only the setting and clearing of the Instruction Register (IR) and Data Register (DR).
Verbs
The following verbs are supported.
| Hex | #define | Description |
|---|---|---|
| 0x10 | SETUP | Configure I/O pins. |
| 0x20 | START | Start a transaction. |
| 0x21 | STOP | Stop a transaction. |
| 0x7E | NOK | No Operation |
| 0x80 | IR_SHIFT | Shift the IR. |
| 0x81 | DR_SHIFT | Shift the DR. |
| 0x91 | DR_SHIFT20 | Shift 20 bits of DR. |