w83l519d Winbond Electronics Corp America, w83l519d Datasheet - Page 12

• Manufacturer Part Number: w83l519d
• Description: Integrated Media Reader
• Manufacturer: Winbond Electronics Corp America

5.2.2
5.2.3
5.3
The trademarks and intellectual property rights of Memory Stick belong to SONY Corporation
The trademarks and intellectual property rights of SD belong to SD GROUP
All trademarks and brand names belong to their respective owners
After programming of the configuration register is completed, another specific value (AAh) should be
written to EFER to leave Extended Function mode to prevent inadvertent accesses to those
configuration registers. User may write a "1" to bit 5 of CR26 (LOCKREG) to prevent configuration
registers from accidental accesses.
After a power-on reset, W83L518D/W83L519D enters the default operation mode. A specific value
must be programmed into the Extended Function Enable Register (EFER) so that configuration
registers can be accessed. On a PC/AT system, its I/O address is 2Eh or 4Eh (as described in
previous section).
After entering Extended Function mode, Extended Function Index Register (EFIR) must be written
with an index value (02h, 07h-FEh) to specify which configuration register is to be accessed through
Extended Function Data Register (EFDR). EFIR is a write-only register at I/O address 2Eh or 4Eh
(as described in section 6.2.1) on a PC/AT system and EFDR is a read/write register at I/O address
2Fh or 4Fh.
To program configuration registers, specific configuration sequence must be followed:
(1) Write 83h to EFER twice to enter Extended Function mode.
(2) Select logical device select register by writing 07h to EFIR.
(3) Select logical device by writing a value to EFDR.
(4) Select control/configuration register by writing its index to EFIR.
(5) Access selected control/configuration register through EFDR.
(6) Repeat step 4 ~ 5 as needed.
(7) Leave Extended Function mode by writing AAh to EFER.
Step 2 and step 3 are not necessary for accessing global register (index 00h to 2Fh).
Configuration Sequence
Extended Functions Enable Register (EFER)
Extended Function Index Register (EFIR), Extended Function Data Register (EFDR)
11
Publication Release Date: Jul. 2002
W83L519D
Revision 1.0