C8051F000/1/2/5/6/7
C8051F010/1/2/5/6/7
21.1.
Boundary Scan
The Data Register in the Boundary Scan path is an 87-bit shift register. The Boundary DR provides control and
observability of all the device pins as well as the SFR bus and Weak Pullup feature via the EXTEST and SAMPLE
commands.
Table 21.1. Boundary Data Register Bit Definitions
EXTEST provides access to both capture and update actions, while Sample only performs a capture.
Bit
0
Action
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Capture
Update
Target
Reset Enable from MCU
Reset Enable to /RST pin
Reset input from /RST pin
Reset output to /RST pin
External Clock from XTAL1 pin
Not used
Weak pullup enable from MCU
Weak pullup enable to Port Pins
SFR Address Bus bit from CIP-51 (e.g. Bit4=SFRA0, Bit5=SFRA1…)
SFR Address Bus bit to SFR Address Bus (e.g. Bit4=XSFRA0, Bit5=XSFRA1)
SFR Data Bus bit read from SFR (e.g. Bit12=SFRD0, Bit13=SFRD1…)
SFR Data Bus bit written to SFR (e.g. Bit12=SFRD0, Bit13=SFRD1…)
SFR Write Strobe from CIP-51
SFR Write Strobe to SFR Bus
SFR Read Strobe from CIP-51
SFR Read Strobe to SFR Bus
SFR Read/Modify/Write Strobe from CIP-51
SFR Read/Modify/Write Strobe to SFR Bus
P0.n output enable from MCU (e.g. Bit23=P0.0, Bit25=P0.1, etc.)
P0.n output enable to pin (e.g. Bit23=P0.0oe, Bit25=P0.1oe, etc.)
P0.n input from pin (e.g. Bit24=P0.0, Bit26=P0.1, etc.)
P0.n output to pin (e.g. Bit24=P0.0, Bit26=P0.1, etc.)
P1.n output enable from MCU (e.g. Bit39=P1.0, Bit41=P1.1, etc.)
P1.n output enable to pin (e.g. Bit39=P1.0oe, Bit41=P1.1oe, etc.)
P1.n input from pin (e.g. Bit40=P1.0, Bit42=P1.1, etc.)
P1.n output to pin (e.g. Bit40=P1.0, Bit42=P1.1, etc.)
P2.n output enable from MCU (e.g. Bit55=P2.0, Bit57=P2.1, etc.)
P2.n output enable to pin (e.g. Bit55=P2.0oe, Bit57=P2.1oe, etc.)
P2.n input from pin (e.g. Bit56=P2.0, Bit58=P2.1, etc.)
P2.n output to pin (e.g. Bit56=P2.0, Bit58=P2.1, etc.)
P3.n output enable from MCU (e.g. Bit71=P3.0, Bit73=P3.1, etc.)
P3.n output enable to pin (e.g. Bit71=P3.0oe, Bit73=P3.1oe, etc.)
P3.n input from pin (e.g. Bit72=P3.0, Bit74=P3.1, etc.)
P3.n output to pin (e.g. Bit72=P3.0, Bit74=P3.1, etc.)
1
2
3
4-11
12-19
20
21
22
23,25,27,29,
31,33,35,37
24,26,28,30,
32,34,36,38
39,41,43,45,
47,49,51,53
40,42,44,46,
48,50,52,54
55,57,59,61,
63,65,67,69
56,58,60,62,
64,66,68,70
71,73,75,77,
79,81,83,85
72,74,76,78,
80,82,84,86
165
Rev. 1.7
SILABS [ SILICON LABORATORIES ]
