Mips Technologies R4000 - Page 427

MIPS R4000 Microprocessor User's Manual 397
JTAG Interface
• When the TAP controller is in the Shift-DR (Boundary-scan)
state, data is serially shifted into the Boundary-scan register
from the JTDI pin, and the contents of the Boundary-scan
register are serially shifted onto the JTDO pin.
• When the TAP controller is in the Update-IR state, the current
data in the shift register stage is loaded into the parallel output
latch.
• When the TAP controller is in the Update-DR (Boundary-scan)
state, data in the Boundary-scan register is latched into the
register parallel output latch. Bits corresponding to output
pins, and those I/O pins whose outputs are enabled (by the
three MSBs of the Boundary-scan register), are loaded onto the
processor pins.
Table 14-2 shows the boundary scan order of the processor signals.
Table 14-2 JTAG Scan Order of R4000 Processor Pins
Pin # Signal Name Pin # Signal Name Pin # Signal Name Pin # Signal Name
1. SCDChk(13) 2. SysADC(1) 3. SCDChk(1) 4. SysADC(5)
5. SCDChk(5) 6. Status(0) 7. Status(1) 8. Status(2)
9. Status(3) 10. IvdErr* 11. Status(4) 12. IvdAck*
13. Status(5) 14. Status(6) 15. Status(7) 16. SCDChk(7)
17. SysADC(7) 18. SCDChk(3) 19. SysADC(3) 20. SCDChk(15)
21. VCCOk 22. SCTag(16) 23. SCDChk(11) 24. SCData(63)
25. SysAD(63) 26. SCData(31) 27. SysAD(31) 28. SCData(127)
29. SCTag(17) 30. SCData(95) 31. SCData(62) 32. SysAD(62)
33. SCData(30) 34. SysAD(30) 35. SCData(126) 36. SCTag(18)
37. SCData(94) 38. RClock(1:0) (share
the same JTAG bit)
39. SCTag(19) 40. SCData(61)
41. SysAD(61) 42. SCData(29) 43. SysAD(29) 44. SCData(125)
45. Reset* 46. SCTag(20) 47. SCData(93) 48. SCData(60)
49. SysAD(60) 50. SCData(28) 51. SysAD(28) 52. SCData(124)
53. ColdReset* 54. SCTag(21) 55. SCData(92) 56. SCData(59)
57. SysAD(59) 58. SCData(27) 59. SysAD(27) 60. SCData(123)
61. IOIn 62. SCTag(22) 63. SCData(91) 64. SCData(58)
65. SysAD(58) 66. SCData(26) 67. SysAD(26) 68. SCData(122)
69. IOOut 70. SCTag(23) 71. SCData(90) 72. SCData(57)
73. SysAD(57) 74. SCData(25) 75. SysAD(25) 76. SCData(121)
77. GrpRun* 78. SCTag(24) 79. SCData(89) 80. SCData(56)
81. SysAD(56) 82. SCData(24) 83. SysAD(24) 84. SCData(120)
85. GrpStall* 86. SCTChk(0) 87. SCData(88) 88. SCDChk(6)
89. SysADC(6) 90. SCDChk(2) 91. SysADC(2) 92. SCDChk(14)
93. NMI* 94. SCTChk(1) 95. SCDChk(10) 96. SCData(55)