Atmel XMEGA-A1 Xplained Evaluation Board ATAVRXPLAIN ATAVRXPLAIN Hoja De Datos

 

8370C-AVR-12/11 

The Atmel XMEGA-A1 Xplained kit has five 10-pin, 100mil headers. One header is 
used for programming the Atmel ATxmega128A1, and the others are used to access 
spare analog and digital pins on the XMEGA (expansion headers). 

The XMEGA can be programmed and debugged by connecting an external 
programming/debugging tool to the JTAG and PDI header (J201). The header has a 
standard JTAG programmer pin-out (refer to online help in the Atmel AVR Studio), 
and tools like the JTAGICE mkII or AVR ONE! can thus be connected directly to the 
header. If it is desired to use PDI programming/debugging, an adapter must be used. 

Due to physical differences of the JTAGICE mkII and AVR ONE! probes, the PCB has 
an opening below the JTAG and PDI header. This is to make room for the orientation 
tap on the JTAGICE mkII probe. 

Because JTAG TDO and PDI DATA are connected on the PCB for this kit, JTAG 
must be disabled on the device in order to use PDI. The reason for this is that when 
JTAG is enabled it will enable a pull-up internally on TDO which interferes with the 
PDI initialization sequence. 

The connection of JTAG_TDO with PDI_DATA is also an issue when the application 
on the device uses the JTAG_TDO pin e.g. by driving this pin actively or by using a 
pull-up. This will interfere with ongoing PDI communication. Additionally, when JTAG 
is disabled and the application is driving the JTAG_TDO pin it might even be not 
possible to establish a PDI connection. A workaround for this is to add a ~1k resistor 
from PDI_CLK/RESET to GND. This will keep the device in reset while PDI is 
enabled. When a PDI connection is established the flash can be erased or JTAG can 
be enabled in order to "unlock" the kit. 

Table 4-1. XMEGA programming and debugging interface – JTAG and PDI. 

1 TCK 

- 

2 GND 

GND 

(3)

 

3 TDO 

DATA 

4 VCC 

VCC 

(3)

 

5 TMS 

- 

6 nSRST 

CLK 

7 -  - 

8 -  - 

9 TDI 

- 

10 GND 

GND 

(3)

 

Notes: 

1.  Standard pin-out for JTAGICE mkII and other Atmel programming tools. 

2.  Requires adapter to connect a JTAGICE mkII (refer to AVR Studio help). 

3.  It is only required to connect on VCC/GND pin. 

The Atmel AT32UC3B1256 can be programmed through its boot loader. The boot 
loader is evoked by shorting the J600 jumper before applying power to the board. The