DSPIC30F2012-20I/SO Microchip Technology, DSPIC30F2012-20I/SO Datasheet - Page 45

• Manufacturer Part Number: DSPIC30F2012-20I/SO
• Description: IC DSPIC MCU/DSP 12K 28SOIC
• Manufacturer: Microchip Technology
• Series: dsPIC™ 30Fr

Specifications of DSPIC30F2012-20I/SO

• Core Processor: dsPIC
• Core Size: 16-Bit
• Speed: 20 MIPS
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 20
• Program Memory Size: 12KB (4K x 24)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.5 V ~ 5.5 V
• Data Converters: A/D 10x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC (7.5mm Width)
• Core Frequency: 40MHz
• Embedded Interface Type: I2C, SPI, UART
• No. Of I/o's: 20
• Flash Memory Size: 12KB
• Supply Voltage Range: 2.5V To 5.5V
• Operating Temperature Range: -40°C To +85°C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: XLT28SO-1 - SOCKET TRANSITION 28SOIC 300MIL
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: DSPIC30F201220ISO

4.2.1
The modulo addressing scheme requires that a starting
and an ending address be specified and loaded
into the 16-bit
XMODSRT, XMODEND, YMODSRT and YMODEND
(see Table 3-3).
The length of a circular buffer is not directly specified. It
is determined by the difference between the corre-
sponding start and end addresses. The maximum pos-
sible length of the circular buffer is 32K words
(64 Kbytes).
© 2005 Microchip Technology Inc.
Note:
Byte
Address
0x1100
0x1163
START AND END ADDRESS
Y space modulo addressing EA calcula-
tions assume word sized data (LS bit of
every EA is always clear).
Start Addr = 0x1100
End Addr = 0x1163
Length = 0x0032 words
Modulo
Buffer
Address
dsPIC30F2011/2012/3012/3013
registers:
MOV
MOV
MOV
MOV
MOV
MOV
MOV
MOV
DO
MOV
AGAIN: INC
Preliminary
#0x1100,W0
W0,XMODSRT
#0x1163,W0
W0,MODEND
#0x8001,W0
W0,MODCON
#0x0000,W0
#0x1110,W1
AGAIN,#0x31
W0,[W1++]
W0,W0
4.2.2
The Modulo and Bit-Reversed Addressing Control reg-
ister MODCON<15:0> contains enable flags as well as
a W register field to specify the W address registers.
The XWM and YWM fields select which registers will
operate with modulo addressing. If XWM = 15, X
RAGU and X WAGU modulo addressing is disabled.
Similarly, if YWM = 15, Y AGU modulo addressing is
disabled.
The X Address Space Pointer W register (XWM), to
which modulo addressing is to be applied, is stored in
MODCON<3:0> (see Table 3-3). Modulo addressing is
enabled for X data space when XWM is set to any value
other than ‘15’ and the XMODEN bit is set at
MODCON<15>.
The Y Address Space Pointer W register (YWM), to
which modulo addressing is to be applied, is stored in
MODCON<7:4>. Modulo addressing is enabled for Y
data space when YWM is set to any value other than
‘15’ and the YMODEN bit is set at MODCON<14>.
FIGURE 4-1:
;set modulo start address
;set modulo end address
;enable W1, X AGU for modulo
;W0 holds buffer fill value
;point W1 to buffer
;fill the 50 buffer locations
;fill the next location
;increment the fill value
W ADDRESS REGISTER
SELECTION
MODULO ADDRESSING
OPERATION EXAMPLE
DS70139C-page 43