DSPIC30F3010-20E/ML Microchip Technology, DSPIC30F3010-20E/ML Datasheet - Page 12
![IC,DSP,16-BIT,CMOS,LLCC,44PIN,PLASTIC](/photos/6/81/68122/150-44-qfn_sml.jpg)
DSPIC30F3010-20E/ML
Manufacturer Part Number
DSPIC30F3010-20E/ML
Description
IC,DSP,16-BIT,CMOS,LLCC,44PIN,PLASTIC
Manufacturer
Microchip Technology
Series
dsPIC™ 30Fr
Datasheets
1.DSPIC30F2011-20ISO.pdf
(66 pages)
2.DSPIC30F2011-20IP.pdf
(26 pages)
3.DSPIC30F3010-30ISO.pdf
(228 pages)
4.DSPIC30F3010-30ISO.pdf
(18 pages)
5.DSPIC30F3010-30ISO.pdf
(6 pages)
6.DSPIC30F3010-30ISO.pdf
(16 pages)
7.DSPIC30F3010-30ISO.pdf
(22 pages)
Specifications of DSPIC30F3010-20E/ML
Rohs Compliant
YES
Core Processor
dsPIC
Core Size
16-Bit
Speed
20 MIPS
Connectivity
I²C, SPI, UART/USART
Peripherals
Brown-out Detect/Reset, Motor Control PWM, QEI, POR, PWM, WDT
Number Of I /o
20
Program Memory Size
24KB (8K x 24)
Program Memory Type
FLASH
Eeprom Size
1K x 8
Ram Size
1K x 8
Voltage - Supply (vcc/vdd)
2.5 V ~ 5.5 V
Data Converters
A/D 6x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 125°C
Package / Case
44-QFN
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
For Use With
XLT44QFN4 - SOCKET TRANS ICE 28DIP TO 44QFN
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
dsPIC30F3010/3011
16. Module: QEI
EXAMPLE 9:
DS80449D-page 12
unsigned int POSCNT_b15 = 0;
unsigned int Motor_Position = 0;
int main(void)
{
}
void __attribute__((__interrupt__)) _QEIInterrupt(void)
{
}
The QEI module does not generate an interrupt
when MAXCNT is set to 0xFFFF and the following
events occur:
1. POSCNT underflows from 0x0000 to 0xFFFF.
2. POSCNT stops.
3. POSCNT overflows from 0xFFFF to 0x0000.
This sequence of events occurs when the motor is
running in one direction, which causes POSCNT to
underflow to 0xFFFF. Once this happens, the
motor stops and starts to run in the opposite
direction, which generates an overflow from
0xFFFF to 0x0000. The QEI module does not
generate an interrupt when this condition occurs.
// ... User's code
MAXCNT = 0x7FFF;
Motor_Position = POSCNT_b15 + POSCNT;
// ... User's code
IFSxbits.QEIIF = 0;
POSCNT_b15 ^= 0x8000; // Overflow or Underflow
// Instead of 0xFFFF
// Clear QEI interrupt flag
// x=2 for dsPIC30F
// x=3 for dsPIC33F
Work around
To prevent this condition from occurring, set
MAXCNT to 0x7FFF, which will cause an interrupt
to be generated by the QEI module.
In addition, a global variable could be used to keep
track of bit 15, so that when an overflow or
underflow condition is present on POSCNT, the
variable will toggle bit 15. Example 9 shows the
code required for this global variable.
Affected Silicon Revisions
A0
X
A1
X
A2
X
© 2010 Microchip Technology Inc.