
Appendix C. Processor Upgrade Suggestions
C-3
CKSTP_IN is referred to as CKSTP on earlier versions of the 603. Likewise,
CKSTP_OUT is referred to as CHECKSTOP.
Processors may have different strappings on PLL_CFG. Programmability on the
upgrade socket is recommended.
ANALOG VDD inputs on the two processors should each have dedicated filter
network.
Connection of TRST, TDI, TDO, TMS, and TCK is a function of system JTAG
testing requirements.
Pull-up L1_TEST_CLK, L2_TEST_CLK, and LSSD_MODE on the 603 and
L1_TEST_CLK, L2_TEST_CLK, LSSD_MODE, and ARRAY_WR on the
upgrade socket.
C.3 PowerPC 604 Processor Upgrade to 60x
The following describes the recommended connection to provide for upgrades from 604 to
future processors:
Pin 275 is ordinarily an OGND signal. Instead of connecting it to ground, use it as
negative true output UPGRADE_SENSE to indicate presence of upgrade processor.
Put a pullup resistor on UPGRADE_SENSE.
On BGA module, use any ground as upgrade sense
If the system does not use the CKSTP_IN input, use a pull-up resister. A gate is not
required.
Connect the following signals in parallel: BR, BG, TS, XATS, ABB, A[0–31],
AACK, AP
n
, APE, TT
n
, TC
n
, TSIZ
n
, TBST, CI, WT, GBL, SHD, ARTRY, DBG,
DBWO, DBB, DH, DL, DBDIS, DP
n
, DPE, TA, DRTRY, TEA, INT, SMI, MCP,
SRESET, HRESET, RSRV, TBEN, and SYSCLK.
No connection necessary for CLKOUT (test only).
Processors may have different strappings on PLL_CFG. Programmability on
upgrade socket is recommended.
ANALOG VDD inputs on the two processors should each have dedicated filter
network.
Connection of TRST, TDI, TDO, TMS, and TCK is a function of system JTAG
testing requirements.
Pull up L1_TEST_CLK, L2_TEST_CLK, LSSD_MODE, and ARRAY_WR on
both processors.