©

©

©

© 2001 Advanced Linear Devices, Inc., 415 Tasman Drive, Sunnyvale, California 94089-1706, Tel: (408) 747-1155, Fax: (408) 747-1286

ALD523D

12/01

13 of 20

EEPROM MEMORY

The ALD523D is organized to operate in conjunction with

a 1K (128 bytes x 8 bits) bi-directional two-wire serial

interface protocol EEPROM memory with page write (8

bytes) capability and has a typical 2 ms write cycle time

for page write, i.e. the 24LC01B or compatible. The

ALD523D stores its setup parameters and arithmetic

parameters at specific memory address locations of the

EEPROM.

These parameters are transferred from

DVM523.EXE PC software to the internal registers of the

ALD523D via a standard PC parallel printer port, and are

page written to the EEPROM from the ALD523D’s

internal registers via serial address/data I/O (SDA) and

serial clock (SCL) lines. Once initiated, all data transfers

between the PC to ALD523D and then to the EEPROM

are performed on a handshake basis automatically.

The

setup parameters are predefined inside the .CDS file,

where the arithmetic parameters are obtained from

calibration process and/or conversion factor scaling.

DATA TRANSFER MODE FROM PC TO ALD523D

The setup parameters and arithmetic parameters of the

ALD523D are stored at the specific memory address

locations as depicted in Table 1 of the ALD523D Setup

and Calibration Software User Guide, and uploaded to the

EEPROM from PC via a parallel printer port (see Upload

Page 1 To 6 (#4 Key) or Upload Page 1 To 13 (#5Key) To

Memory section in the ALD523D Setup and Calibration

Software User Guide on how to upload EEPROM via

DVM523.EXE). The block diagram of the data transfer

mode is shown in figure 7.

Figure 7. Data transfer mode block diagram.

Upon power up or during normal running condition, the

ALD523D continuously checks the status of DVCS and

CAL, respectively for the setup and calibration mode. A

logical “0” state on DVCS pin with a logical “0” on CAL

pin set by the PC put the ALD523D in the Data Transfer

from PC mode.

In this mode, a message “UPLOAD MEMORY” is

displayed on the Characters Display Module (CDM) to

indicate the ALD523D is in data transfer mode.

Parameters for uploading EEPROM are transferred from

the PC to ALD523D serially via the SCLK and DATIN

pins, with 8 bytes of 8-bit data (total of 64 bits) as 1 page

of data.

Initially, the bit and page counters within the ALD523D

and the PC are set to 1, and the DVCS pin is set to logic

“0” state with the first bit of the serial data transmitted

simultaneously via DATIN pin. The ALD523D reads the

first bit on DATIN and sends a serial clock pulse on the

SCLK as the acknowledge signal. This serial data upload

process continues for the rest of the 64 serial bits with

alternatively receiving the DVCS pulses from the PC and

sending the corresponding serial clock pulses on every bit

read, until the bit counter is set to 64 along with DVCS set

to logic “1” state, which then are in turn uploaded into the

EEPROM automatically by the ALD523D, using the page

write mode.

Then the page counter is advanced to the second page, and

the PC puts out a second DVCS logic “0” state, and begins

the transfer of the next 8 bytes of 8-bit data. Through the

repeated serial clock and data valid handshakes via DVCS

and SCLK pins, either 6 pages or 13 pages of 8 bytes of 8-

bit serial data are transmitted via DATIN pin into

ALD523D’s internal registers. This uploading process is

fully automatic.

The 64-bit serial clock pulses transmit 64-bit binary data

with bit 63 as the first bit and bit 0 as the last bit. The

detailed timing is shown in “Data Transfer From PC”

section of this data sheet. Once the PC sets the CAL pin to

logic “1” at the end of setup mode, the ALD523D returns

to its normal running mode.

ALD523D

1K

EEPROM

PC

INTERFACE