DS4550 Maxim, DS4550 Datasheet - Page 13

• Manufacturer Part Number: DS4550
• Description: The DS4550 is a 9-bit, nonvolatile (NV) I/O expander with 64 bytes of NV user memory controlled by either an I²C-compatible serial interface or an IEEE® 1149
• Manufacturer: Maxim

Table
Table
NUMBER
EEPROM
EEPROM
Address
Register
Address
Register
Select
Select
CELL
STEP
Load
Read
Read
Data
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
3. Boundary Scan Control Bits [33 Bits]
4. EEPROM Read Cycle
Select-IR-Scan
Capture-IR
Shift-IR (4 x TCK)
Exit1-IR
Update-IR
Select-DR-Scan
Capture-DR
Shift-DR (8 x TCK)
Exit1-DR
Update-DR
Select-IR-Scan
Capture-IR
Shift-IR (4 x TCK)
Exit1-IR
Update-IR
Select-DR-Scan
Capture-DR
Shift-DR (8 x TCK)
Exit1-DR
Update-DR
SDA output
IO8 pubout
IO8 pdbout
IO7 pubout
IO7 pdbout
IO6 pubout
IO6 pdbout
IO5 pubout
IO5 pdbout
SDA input
SCL input
IO8 input
IO7 input
IO6 input
A2 input
A1 input
A0 input
NAME
TAP STATE
I
Input Observe Only
Input Observe Only
Input Observe Only
Input Observe Only
Input Observe Only
Input Observe Only
Input Observe Only
Input Observe Only
2
C and JTAG Nonvolatile 9-Bit I/O
____________________________________________________________________
Output
Output
Output
Output
Output
Output
Output
Output
Output
TYPE


The 4-bit instruction is shifted in through TDI.



No-op.
The 8-bit address is shifted in through TDI.

The shifted 8-bit Address Register data is output latched.


The 4-bit instruction is shifted in through TDI.



The 8-bit EEPROM data is loaded into the EEPROM Read Register.
The 8-bit data is shifted out through TDO.

No-op.
Expander Plus Memory
NUMBER
CELL
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
COMMENTS
IO4 pubout
IO4 pdbout
IO3 pubout
IO3 pdbout
IO2 pubout
IO2 pdbout
IO1 pubout
IO1 pdbout
IO0 pubout
IO0 pdbout
IO5 input
IO4 input
IO3 input
IO2 input
IO1 input
IO0 input
NAME
Input Observe Only
Input Observe Only
Input Observe Only
Input Observe Only
Input Observe Only
Input Observe Only
Output
Output
Output
Output
Output
Output
Output
Output
Output
Output
TYPE
13