ColdFire BDM connector information

The CodeWarrior Ethernet TAP ColdFire BDM probe has a 26-pin connector which automatically supports target system signal levels from 1.8V to 3.3V.

The following figure shows the pin assignments of the probe BDM connector.

Figure 1. Ethernet TAP probe ColdFire BDM connector pin assignments

The following table lists BDM signal names, direction, pin numbers, descriptions, and drive capabilities of the probe BDM connector.

Table 1. Ethernet TAP probe ColdFire BDM signal directions
BDM pin	Signal mnemonic	Signal direction	Description
1	Reserved	From target system	17pF load
2	BKPT	From Ethernet TAP probe connector	50mA driver
3	GND	- n/a -
4	DSCLK	From Ethernet TAP probe connector	50mA driver
5	GND	- n/a -
6	Reserved	Bi-directional	Open-drain, 100Ohm to ground when asserted by Ethernet TAP probe, 22pF load when not asserted
7	RESET	Bi-directional	Open-drain. 100Ohm to ground when asserted by Ethernet TAP probe, 22pF load when not asserted¹
8	DSI	From Ethernet TAP probe connector	50mA driver
9	VDD	From target system	2MOhm pull-down, plus 0.01uF load
10	DSO	From target system	17pF load
11	GND	- n/a -
12	PST3	- n/a -
13	PST2	- n/a -
14	PST1	- n/a -
15	PST0	- n/a -
16	DDATA3	- n/a -
17	DDATA2	- n/a -
18	DDATA1	- n/a -
19	DDATA0	- n/a -
20	GND	- n/a -
21	Reserved	- n/a -
22	Reserved	- n/a -
23	GND	- n/a -
24	PSTCLK	From target system	17pF load
25	Core Voltage	- n/a -
26	TEA	From Ethernet TAP probe connector	50mA driver¹

The table below provides a general description of each BDM signal and operational requirements.

Note: All ColdFire BDM signals must meet accepted standards for ColdFire BDM signal design. To ensure proper and stable operation between the Ethernet TAP probe and the target system, the BDM signals must meet the requirements listed in the following table.

Table 2. Ethernet TAP probe ColdFire BDM signal recommendations and requirements
BDM pin	Signal mnemonic	Requirement
1	Reserved	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
2	BKPT	Must be wired to the target system.
3	GND	Must be wired to the target system. GND is connected directly to the ground inside the Ethernet TAP probe.
4	DSCLK	DSCLK must be connected to the target system's processor. It is driven by the Ethernet TAP probe as an output with up to 50mA. This signal is the clock for the BDM interface. It is good design practice to keep the trace length short and isolate the trace from other signals. If the trace must be long, then termination may be needed.
5	GND	Must be wired to the target system. GND is connected directly to the ground inside the Ethernet TAP probe.
6	Reserved	Need not be wired to the target system. The Ethernet TAP does not currently use this signal.
7	RESET	Must be wired to the target system. During reset, the Ethernet TAP probe drives RESET to ground through a 100Ohm resistor.
8	DSI	Must be wired to the target system processor. The Ethernet TAP probe drives the DSI output with up to 50mA.
9	VDD	Must be wired to the target system. The Ethernet TAP probe uses this signal to determine if power is applied to the target system. The signal is also used as a voltage reference for the signals driven by the Ethernet TAP probe (BKPT, DSCLK, RESET, DSI, and TEA).
10	DSO	Must be wired to the target system processor. It is an input to the Ethernet TAP probe.
11	GND	Must be wired to the target system. GND is connected directly to the ground inside the Ethernet TAP probe.
12	PST3	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
13	PST2	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
14	PST1	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
15	PST0	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
16	DDATA3	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
17	DDATA2	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
18	DDATA1	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
19	DDATA0	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
20	GND	Must be wired to the target system. GND is connected directly the ground inside the Ethernet TAP probe.
21	Reserved	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
22	Reserved	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
23	GND	Must be wired to the target system. GND is connected directly to the ground inside the Ethernet TAP probe.
24	PSTCLK	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
25	Core Voltage	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.
26	TEA	Need not be wired to the target system. The Ethernet TAP probe does not currently use this signal.