MC9RS08KA2 Datasheet, PDF (103/132 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 12 Development Support
15
R0
W
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0
Any
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 12-7. BDC Breakpoint Match Register (BDCBKPT)
12.5 RS08 BDC Commands
BDC commands are sent serially from a host computer to the BKGD pin of the target MCU. All commands
and data are sent MSB-first using a custom BDC communications protocol. Active background mode
commands require that the target MCU is currently in the active background mode while non-intrusive
commands may be issued at any time whether the target MCU is in active background mode or running a
user application program.
Table 12-2 shows all RS08 BDC commands, a shorthand description of their coding structure, and the
meaning of each command.
Coding Structure Nomenclature
The following nomenclature is used in Table 12-2 to describe the coding structure of the BDC commands.
Commands begin with an 8-bit command code in the host-to-target direction
(most significant bit first)
/ = Separates parts of the command
d = Delay 16 to 511 target BDC clock cycles
soft-reset = Delay of at least 512 BDC clock cycles from last host falling-edge
AAAA = 16-bit address in the host-to-target direction¹
RD = Eight bits of read data in the target-to-host direction
WD = Eight bits of write data in the host-to-target direction
RD16 = 16 bits of read data in the target-to-host direction
WD16 = 16 bits of write data in the host-to-target direction
SS = the contents of BDCSCR in the target-to-host direction (STATUS)
CC = Eight bits of write data for BDCSCR in the host-to-target direction (CONTROL)
RBKP = 16 bits of read data in the target-to-host direction (from BDCBKPT breakpoint
register)
WBKP = 16 bits of write data in the host-to-target direction (for BDCBKPT breakpoint
register)
1. The RS08 CPU uses only 14 bits of address and occupies the lower 14 bits of the 16-bit AAAA address field. The values of
address bits 15 and 14 in AAAA are truncated and thus do not matter.
MC9RS08KA2 Series Data Sheet, Rev. 2
Freescale Semiconductor
103