ADUC814BRU Analog Devices Inc, ADUC814BRU Datasheet - Page 33

• Manufacturer Part Number: ADUC814BRU
• Description: A/D Converter (A-D) IC
• Manufacturer: Analog Devices Inc
• Series: MicroConverter® ADuC8xxr

Specifications of ADUC814BRU

• Peak Reflow Compatible (260 C): No
• No. Of Bits: 12 Bit
• Leaded Process Compatible: No
• Mounting Type: Surface Mount
• No. Of Inputs: 6
• Features: +3V Or +5V Operation
• Package / Case: 28-TSSOP
• Rohs Status: RoHS non-compliant
• Core Processor: 8052
• Core Size: 8-Bit
• Speed: 16.78MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: POR, PSM, Temp Sensor, WDT
• Number Of I /o: 17
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 640 x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 6x12b; D/A 2x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With: EVAL-ADUC814QSZ - KIT DEV FOR ADUC814 MICROCONVRTR
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

FLASH/EE MEMORY TIMING
The typical program/erase times for the Flash/EE data memory
are
Erase Full Array (640 bytes)
Erase Single Page (4 bytes)
Program Page (4 bytes)
Read Page (4 bytes)
Using the Flash/EE Memory Interface
As with all Flash/EE memory architectures, the array can be
programmed in-system at a byte level, although it must be
erased first, the erasure being performed in page blocks (4-byte
pages in this case).
A typical access to the Flash/EE data array involves setting up
the page address to be accessed in the EADRL SFR, configuring
the EDATA1–4 with data to be programmed to the array (the
EDATA SFRs are not written to for read accesses), and finally,
writing the ECON command word, which initiates one of the
modes shown Table 11.
Note that a given mode of operation is initiated as soon as the
command word is written to the ECON SFR. The core micro-
controller operation on the ADuC814 is idled until the
requested program/read or erase mode is completed. In
practice, this means that even though the Flash/EE memory
mode of operation is typically initiated with a two-machine
cycle MOV instruction (to write to the ECON SFR), the next
instruction cannot be executed until the Flash/EE operation is
complete (250 µs or 2 ms later). This means that the core does
not respond to interrupt requests until the Flash/EE operation is
complete, though the core peripheral functions like counter/
timers continue to count and time as configured throughout
this period. Although the 640-byte user Flash/EE array is
2 ms
2 ms
250 µs
Within single instruction cycle
Rev. A | Page 33 of 72
shipped from the factory pre-erased, i.e., byte locations set to
FFH, it is nonetheless good programming practice to include an
ERASE-ALL routine as part of any configuration/setup code
running on the ADuC814. An ERASE-ALL command consists
of writing 06H to the ECON SFR, which initiates an erasure of
all 640 byte locations in the Flash/EE array. This command
coded in 8051 assembly appears as
MOV ECON, #06H
Programming a Byte
In general terms, a byte in the Flash/EE array can be programmed
only if it has been erased previously. To be more specific, a byte
can only be programmed if it already holds the value FFH.
Because of the Flash/EE architecture, this erasure must happen
at a page level; therefore, a minimum of four bytes (1 page) are
erased when an ERASE command is initiated.
A more specific example of the program-byte process is shown
below. In this example the user writes F3H into the second byte
on Page 03H of the Flash/EE data memory space while
preserving the other three bytes already in this page. Because
the user is required to modify only one of the page bytes, the
full page must be first read so that this page can then be erased
without the existing data being lost. This example, coded in
8051 assembly, appears as
MOV EADRL,#03H
MOV ECON,#01H
MOV EDATA2,#0F3H
MOV ECON,#05H
MOV ECON,#02H
; Set Page Address
; Pointer
; Read Page
; Write New Byte
; Erase Page
; Write Page
; Program Flash/EE)
; Erase all Command
; 2 ms Duration
ADuC814