S1X60000 Datasheet, PDF (275/358 Pages) Epson Company – EMBEDDED ARRAY

Chapter 10 Circuit Design that Takes Testability into Account
10.8.2 Instructions
The JTAG instructions specified below are supported.
Table 10-4 Supported Instruction Codes
Instruction
SAMPLE/PRELOAD
BYPASS
EXTEST
CLAMP
HighZ
IDCODE
Code
0...10
1...11
0...00
Selectable as desired^(*1)
Selectable as desired^(*1)
0...01
Note
*1: Unless explicitly specified, Epson will select the appropriate code. No duplicate codes can be
specified.
Instruction bit sizes may be selected in the range of 2 to 32 bits. Unless explicitly specified, Epson
will determine the appropriate instruction size.
10.8.3 Estimating the Number of Gates
The extent of the increase in the number of gates as a result of boundary scan insertion
depends on the ASIC series used and the instructions and bit sizes supported. Estimate the
approximate number of gates using the information given below.
Table 10-5 Gate Count Estimation (SOG Equivalent)
Boundary Scan Block
TAP controllers + miscellaneous gates
Input pin
2-state output pin
3-state output pin
Bi-directional pin
Gate Counts
Approx. 1000 (BCs)
When using normal cells: Approx. 30 (BC/pin)
When using dedicated observation cells: Approx. 15 (BC/pin)
Approx. 35 (BC/pin)
Approx. 65 (BC/pin)
Approx. 95 (BC/pin)
10.8.4 Design Rules
For the boundary scan service to be used, it is necessary that customers’ logic circuits be
designed in observance of the restrictions described below. Before releasing data to Epson,
please be sure to confirm the circuit information using the Boundary Scan Checksheet
attached at the end of this chapter, and to fill out and present the Design Information Sheet
to Epson. Please note that if any circuit violating the restrictions exists, this service cannot
be used.
a. Coexistence with DC/AC easy to test circuits inhibited
Coexistence with the easy to test circuits described in Section 10.3, “Test Circuit Which
Simplifies DC and AC Testing,” is inhibited. To be suitable for the boundary scan
service, a design cannot have DC/AC easy to test circuits inserted in it.
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EMBEDDED ARRAY S1X60000 SERIES
DESIGN GUIDE