IEEE 1149.1 Test Access Port Controller (JTAGC)
MPC5606S Microcontroller Reference Manual, Rev. 7
720 Freescale Semiconductor
19.7.4 Boundary Scan register
The boundary scan register is connected between TDI and TDO when the EXTEST, SAMPLE, or
SAMPLE/PRELOAD instructions are active. It is used to capture input pin data, force fixed values on
output pins, and select a logic value and direction for bidirectional pins. Each bit of the boundary scan
register represents a separate boundary scan register cell, as described in the IEEE 1149.1-2001 standard
and discussed in Section 19.8.5, Boundary scan. The size of the boundary scan register is 464 bits.
19.8 Functional description
19.8.1 JTAGC reset configuration
While in reset, the TAP controller is forced into the Test-Logic-Reset state, thus disabling the test logic
and allowing normal operation of the on-chip system logic. In addition, the instruction register is loaded
with the IDCODE instruction.
19.8.2 IEEE 1149.1-2001 (JTAG) Test Access Port
The JTAGC uses the IEEE 1149.1-2001 TAP for accessing registers. This port can be shared with other
TAP controllers on the MCU. For more detail on TAP sharing via JTAGC instructions, refer to
Section 19.8.4.2, ACCESS_AUX_TAP_x instructions.
Data is shifted between TDI and TDO through the selected register starting with the least significant bit,
as illustrated in
Figure 19-4. This applies for the instruction register, test data registers, and the bypass
register.
Figure 19-4. Shifting Data Through a Register
Table 19-2. Device Identification Register field descriptions
Field Description
0–3
PRN
Part revision number. Contains the revision number of the device. This field changes with each revision
of the device or module.
4–9
DC
Design center.
10–19
PIN
Part identification number. Contains the part number of the device.
20–30
MIC
Manufacturer identity code. Contains the reduced Joint Electron Device Engineering Council (JEDEC) ID
for Freescale, 0xE
31
ID
IDCODE register ID. Identifies this register as the device identification register and not the bypass
register. Always set to 1.
Selected register
MSB
LSB
TDI
TDO
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