ald523d Advanced Linear Devices Inc (ALD), ald523d Datasheet - Page 13

• Manufacturer Part Number: ald523d
• Description: Multifunction 7-digit Serial Input Display Module Controller
• Manufacturer: Advanced Linear Devices Inc (ALD)

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.
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.
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.
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.
ALD523D
© © © © 2001 Advanced Linear Devices, Inc., 415 Tasman Drive, Sunnyvale, California 94089-1706, Tel: [phone], Fax: [phone]
INTERFACE
Figure 7. Data transfer mode block diagram.
PC
These parameters are transferred from
12/01
ALD523D
http://www.aldinc.com
EEPROM
The
1K
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.
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