Hi, I have used LM1086-3.3 lowdrop regulator and R8C cpu. Reset circuit is only pull-up. CPU doesn't start up right. External oscillator...

Hi, I have used LM1086-3.3 lowdrop regulator and R8C cpu. Reset circuit is only pull-up. CPU doesn't start up right. External oscillator doesn't run when I turn on power. If I reset the CPU externaly everthing is OK. Can you recommend something?

I have a Olimex devboard AVR-P28B with a ATMEGA8 on it. I programmed and used it just fine when it was running on the internal RC oscillator. But...

I have a Olimex devboard AVR-P28B with a ATMEGA8 on it. I programmed and used it just fine when it was running on the internal RC oscillator. But I wanted to try to get it working on the 4Mhz crystal so I set the fuse bits and wrote those. Problem is, now it doesn't work anymore and I can't get it to respond and change the fuse bits. How can I program the fuse bits in this situation? I assu...

Hello, For many years we are using pic 8 bit micros for our product. We have come to a point we are considering a new solution. The pic...

Hello, For many years we are using pic 8 bit micros for our product. We have come to a point we are considering a new solution. The pic internal oscilator is not accurate enough for our application because it is based on RC technology. We need an internal oscillator because we are becoming very tight in phisical space(volume wise). My Question is. can someone point 8bit mcu with Acuurate In...

I'd like to use async UART to let these MCUs communicate. The protocol will be request-response with the request generated by the SAM MCU. The...

I'd like to use async UART to let these MCUs communicate. The protocol will be request-response with the request generated by the SAM MCU. The baudrate will be 38400bps. I'd like to use internal oscillator of ATtiny4313, while the SAM will use an external 32.768kHz crystal (that is multiplied by internal PLL to reach 48MHz). I'm not sure if this scenario can work well. My concerns are...

Hello, I have a design with 2 clocks provied to my FPGA (Spartan 3-A). The first one comes from an external oscillator @ 50MHZ. The second...

Hello, I have a design with 2 clocks provied to my FPGA (Spartan 3-A). The first one comes from an external oscillator @ 50MHZ. The second one also comes from an external BUS clock (75MHZ). The 75MHZ is the main system clock. It is used to feed an internal AMBA bus. The 50MHZ is needed to compute with precision a frame (customer need) with a very low BER. How can I synchronize those ...

Hello please, can i have some help? For a reason that i still don't know i have that my Kinetis MKL15Z128 is impossible to program or...

Hello please, can i have some help? For a reason that i still don't know i have that my Kinetis MKL15Z128 is impossible to program or debug. It is mounted on an almost-empty board,where i have the uC,with connected and decoupled supplies and GNDs. The programming was done via the SWD interface, SWDIO,SWDCLK,and RST. No crystal oscillator is mounted I have a pulse on the RST pin,36K...

Hello, All! I'm trying to program ATmega162V chip using AVR Studio 4. STK500 board is installed according to manual and i can program the...

Hello, All! I'm trying to program ATmega162V chip using AVR Studio 4. STK500 board is installed according to manual and i can program the sample chip provided with board without any errors or warning, but trying to burn the mega162v i get this error: FLASH contents differs from file Before burning I erased chip succesfully. Oscillator frequency and voltage value are setup by...

Hi, Microchip's datasheet for the pic16f88 says: The PIC16F87/88 oscillator design requires the use of a parallel cut crystal. Use of a...

Hi, Microchip's datasheet for the pic16f88 says: The PIC16F87/88 oscillator design requires the use of a parallel cut crystal. Use of a series cut crystal may give a frequency out of the crystal manufacturer's specifications. So I am choosing a 20MHz Xtal to use. The part I'm looking at is: RAKON -- CRYSTAL, 12SMX (B) 20 MHZ And the datasheet I have for it is here: http://www.farnell.c...

Hello everybody! I have a problem with ATmega168 (will later be an mega88) and PB6/PB7. I'm trying to use these as output pins, ie. drive...

Hello everybody! I have a problem with ATmega168 (will later be an mega88) and PB6/PB7. I'm trying to use these as output pins, ie. drive low-current LEDs by connecting PB6/PB7 via resistor and LED to +5V. That worked very good when I used PD5; but I need the PWM now and wanted to use PB6/PB7. I'm using the internal RC oscillator; timer 2 is currently unused, and if I need it later ...

I have a system that needs to spend the majority of its time in a sleep mode (using internal 30kHz oscillator), wake to respond to some...

I have a system that needs to spend the majority of its time in a sleep mode (using internal 30kHz oscillator), wake to respond to some interrupts (either still running at 30kHz or 6MHz external crystal) and occasionally perform some high speed tasks (using the 6MHz external with a PLL ---> 50MHz). I've neglected my power management to this point and now I am at the tail end of the project looking

Hai to all, Iam trying to communicate from pic 16f877a to the pc's hyperterminal at 9600 baud rate. Iam posting my code for this. Iam able...

Hai to all, Iam trying to communicate from pic 16f877a to the pc's hyperterminal at 9600 baud rate. Iam posting my code for this. Iam able to simulate with mplab but I could not implement with hardware. I checked for max232, rs232. They seem to be working perfect. But iam not getting the data through hyperterminal comm port. My crystal oscillator is 8mhz. /* uart serial communicati...

Robert, Thanks for your last reply. > I thought that your target phase was determined by some external > event. But it is only...

Robert, Thanks for your last reply. > I thought that your target phase was determined by some external > event. But it is only determined by an internal counter. Is anything > else external locked to this reference counter? If not, then I wonder > why you specified an phase lock tolerance of .5 degrees to a reference > that is just an arbirary internal oscillator? The counter is ac

Hi, I am new on this field, and taking this as hobby, but the real fact is, I can't communicate my 8051 microcontroller board to my PC...

Hi, I am new on this field, and taking this as hobby, but the real fact is, I can't communicate my 8051 microcontroller board to my PC via serial port. can any body help me for that issue?? Specification of my board: 8051 microcontroller: AT89C52 24pc. Cristal Oscillator: 11.0592 Mhz. Compiler: Keil. The code for the board: ;------------------------------------------------------...

Hello. I have problem with Monitor Mode in MC68HC908GP32. I try to programme this uC so I use PROG08SZ programmer (on Windows 2003). I made...

Hello. I have problem with Monitor Mode in MC68HC908GP32. I try to programme this uC so I use PROG08SZ programmer (on Windows 2003). I made Normal Monitor Mode Circuit from AN2317/D Application Note (page 9): http://www.freescale.com/files/microcontrollers/doc/app_note/AN2317.pdf but I used a 8 MHz oscillator. My GP32 connections are show below: RST -> Vdd (with pull-up resistor) IRQ

Hi All, To control a RF transmitter, I have to set its synthesizer paramter N: N = (fTX + foffset) / Xclk we know foffset and Xclk, it...

Hi All, To control a RF transmitter, I have to set its synthesizer paramter N: N = (fTX + foffset) / Xclk we know foffset and Xclk, it is easy to get N when I set any fTX. but the problem is, there is a register called: Local oscillator frequency extension. It has 2 bits for different range frequency. Why do I need this? If chip already know my target frequency, why shoul...

I'm wondering if there is some well known issue with the 16F872 WRT using the RC oscillator mode. I was told that the 'F872 was a...

I'm wondering if there is some well known issue with the 16F872 WRT using the RC oscillator mode. I was told that the 'F872 was a pin-compatible replacement for the 'C62B (ignoring the A/D). When the 'C62B is in the socket I get a nice clock out signal on pin 10, CLKOUT. Quickly swapping in the 'F872 I get a DC low-level and pin 9, CLKIN is a DC high-level. Anyone? Thanks. -- - Mark ...

Hi there, I believe it is easy to use a high-end digital oscillator these days to generate a tracking pulse with a few nanoseconds delay...

Hi there, I believe it is easy to use a high-end digital oscillator these days to generate a tracking pulse with a few nanoseconds delay compared to the reference pulse. However, I am thinking about the possibility to implement the task in a different way, a lower-cost way. Last month I designed a small circuit to generate the reference pulse sequence at 35.42MHz with DW9255 (35.42M cent...

Has anyone used the CCS C compiler with the PIC12CE674? I'm having difficulty getting out of the starting block with a simple program...

Has anyone used the CCS C compiler with the PIC12CE674? I'm having difficulty getting out of the starting block with a simple program (attached). The chip is supposed to be set up to run on the internal oscillator (at 4MHz) with the OSC2 pin set as an IO line, no MCLR pin input (MCLR pin used as an IO line), and with AN0 and AN1 used as analog inputs. I've verified the fuse settings...

I've been using avr for quite some time now, but recently I encountered a problem programming atmega168 using ISP: set up- JTAG ICE mkII, ISP...

I've been using avr for quite some time now, but recently I encountered a problem programming atmega168 using ISP: set up- JTAG ICE mkII, ISP connector to atmega168 atmega168 uses internal oscillator nothing is connected to the reset pin except for the nSRST of mkII. For the first few tries, programming works fine for a fresh chip. The same code can be programmed to the chip more than on...

Hello, I am working with the Maxim/Dallas RTCs which specify a requirement of 6pf load capacitance crystals. I can only source 12pf. It is...

Hello, I am working with the Maxim/Dallas RTCs which specify a requirement of 6pf load capacitance crystals. I can only source 12pf. It is mentioned in the datasheets that a load (12pf) which is greater than what the RTC is designed for (6pf); "If the capacitive load is less than the crystal was designed for, the oscillator runs fast. If the capacitive load is greater than what the crys...