Background Debug Mode (BDM) Interface
MCF5253 Reference Manual, Rev. 1
Freescale Semiconductor
20-9
20.3.2.1
Receive Packet Format
The basic receive packet of information is 17 bits long,16 data bits plus a status bit, as shown in
.
describes the receive BDM packets. Bit descriptions are described in
20.3.2.2
Transmit Packet Format
The basic transmit packet of information is 17 bits long,16 data bits plus a control bit, as shown in
.
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
S
DATA FIELD [15:0]
Figure 20-4. Receive BDM Packet Register
Table 20-2. CPU-Generated Command Responses
S Bit
Data
Message Type
0
xxxx
Valid data transfer
0
$FFFF
Status OK
1
$0000
Not ready with response; try again
1
$0001
Error—terminated bus cycle; data invalid
1
$FFFF
Illegal command
Table 20-3. Receive BDM Packet Register Field Descriptions
Field
Description
16
S-Status
The status bit indicates the status of CPU-generated messages as shown in
.
15–0
Data
The data field contains the message data to be communicated from the debug module to the development
system. The response message is always a single word, with the data field encoded as shown in
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
C
DATA FIELD [15:0]
Figure 20-5. Transmit BDM Packet Register
Table 20-4. Transmit BDM Packet Register Field Descriptions
Field
Description
16
C-Control
The Control Bit (Bit 16) is reserved. Command and data transfers initiated by the development system should
clear bit 16.
15–0
Data Field
The data field contains the message data to be communicated from the development system to the debug
module.
Summary of Contents for MCF5253
Page 1: ...Document Number MCF5253RM Rev 1 08 2008 MCF5253 Reference Manual...
Page 26: ...MCF5253 Reference Manual Rev 1 xxvi Freescale Semiconductor...
Page 32: ...MCF5253 Reference Manual Rev 1 xxxii Freescale Semiconductor...
Page 46: ...MCF5253 Introduction MCF5253 Reference Manual Rev 1 1 14 Freescale Semiconductor...
Page 62: ...Signal Description MCF5253 Reference Manual Rev 1 2 16 Freescale Semiconductor...
Page 98: ...Instruction Cache MCF5253 Reference Manual Rev 1 5 10 Freescale Semiconductor...
Page 104: ...Static RAM SRAM MCF5253 Reference Manual Rev 1 6 6 Freescale Semiconductor...
Page 128: ...Synchronous DRAM Controller Module MCF5253 Reference Manual Rev 1 7 24 Freescale Semiconductor...
Page 144: ...Bus Operation MCF5253 Reference Manual Rev 1 8 16 Freescale Semiconductor...
Page 176: ...System Integration Module SIM MCF5253 Reference Manual Rev 1 9 32 Freescale Semiconductor...
Page 198: ...Analog to Digital Converter ADC MCF5253 Reference Manual Rev 1 12 6 Freescale Semiconductor...
Page 246: ...DMA Controller MCF5253 Reference Manual Rev 1 14 18 Freescale Semiconductor...
Page 282: ...UART Modules MCF5253 Reference Manual Rev 1 15 36 Freescale Semiconductor...
Page 344: ...Audio Interface Module AIM MCF5253 Reference Manual Rev 1 17 46 Freescale Semiconductor...
Page 362: ...I2 C Modules MCF5253 Reference Manual Rev 1 18 18 Freescale Semiconductor...
Page 370: ...Boot ROM MCF5253 Reference Manual Rev 1 19 8 Freescale Semiconductor...