global clock (gclk) input at xilinx virtex4 fpga

Started by Denkedran Joe in comp.arch.embedded12 years ago 2 replies

Hi there, I'm using a Virtex4 FX100 FPGA (package FF1517) in a board design and I wonder if it is enough to use just one gclk input on the...

Hi there, I'm using a Virtex4 FX100 FPGA (package FF1517) in a board design and I wonder if it is enough to use just one gclk input on the device or if it's advisable to use more than one due to the large package size...? Does it make any difference where I put the gclk input(s)? Thank you for your support... Regards Joe


Zilog Z8S180 problems

Started by Mike Harding in comp.arch.embedded15 years ago 6 replies

I seem to be unable to access the new registers on the Zilog Z8S180 CPU, things like the Clock Multiplier register, the additional DMA register...

I seem to be unable to access the new registers on the Zilog Z8S180 CPU, things like the Clock Multiplier register, the additional DMA register etc. When I try to write to these registers my writes seem to be ignored and when I read them back I read FF from most 00 from one. Anyone else having problems with this chip or know the secret code to make it work? :) For all the world it's behaving...


DS1306 RTC Read with HC08 SPI

Started by Thunder in comp.arch.embedded16 years ago 1 reply

Hi, I'm attempting to use a real-time clock (DS1306) by interfacing it with a HC08GP32 microcontroller using the SPI. To get my algorithm...

Hi, I'm attempting to use a real-time clock (DS1306) by interfacing it with a HC08GP32 microcontroller using the SPI. To get my algorithm working, I am using some of the extra RAM located in the DS1306 to write a few registers and then attempt to read them. It seems that the writing part works fine; however, when I attempt to read back what I've written, I get varying results. I'm usi...


Maximum frequency

Started by knight in comp.arch.embedded11 years ago 2 replies

Hi all, Iam using Xilinx XST for synthesis. Iam using almost 20 modules in my design. each if i synthesize seperately iam getting a maximum...

Hi all, Iam using Xilinx XST for synthesis. Iam using almost 20 modules in my design. each if i synthesize seperately iam getting a maximum frequency of more than 400 Mhz. But when i combine everything iam getting only 121Mhz. Can you tell me the reason...??? Does this mean i cannot use a clock more than 121 Mhz in my design(iam using and found it working well..) How can i increase my...


Are watts per MHz linear?

Started by Ghazan Haider in comp.arch.embedded14 years ago 2 replies

In looking at various 32-bit MCUs, I've seen watts per MHz mentioned. A linuxdevices.com news article talks about Powerpc 405: "Power usage...

In looking at various 32-bit MCUs, I've seen watts per MHz mentioned. A linuxdevices.com news article talks about Powerpc 405: "Power usage is listed as 0.2mW/MHz". So lets take the simple PIC. Can I clock it down and watch power usage go down linearly? If a chip is 10mA at 10MHz, will it be 10uA at 10kHz? I take it theres always a base current at DC. so the equation should be (K x MHz) + ...


Generating 6MHz output frequency

Started by djordj in comp.arch.embedded13 years ago 4 replies

I need to drive a 320x240x8bbp TFT color display (Hitachi XT14 series). I need to provide a clock signal @ ~6MHz and I can't use a micro with a...

I need to drive a 320x240x8bbp TFT color display (Hitachi XT14 series). I need to provide a clock signal @ ~6MHz and I can't use a micro with a built in controller. Options are: 1) driving the TFT directly from the microcontroller 2) using an EPSON controller (or a dedicate FPGA) As I have to use STR9 chip, I'm trying to figure out if I can really obtain this output frequency: the pro...


Atmega168 and peripheral interrupts

Started by P.Marek in comp.arch.embedded14 years ago 2 replies

I have a problem with an atmega168. On my test board I have a jumper on PB1 and a LED on PD5, using internal 8MHz RC-clock. Given the...

I have a problem with an atmega168. On my test board I have a jumper on PB1 and a LED on PD5, using internal 8MHz RC-clock. Given the following program: #include #include #include INTERRUPT(SIG_PCINT0) { unsigned short i; char j; for(j=0; j


Atmega8-L at 8MHz internal oscíllator not stable?

Started by Antti in comp.arch.embedded7 years ago 8 replies

Hi I am not believing what I see, but I have a board where ATmega8L doesnt want to work with 8MHz internal oscillator setting - the datasheet...

Hi I am not believing what I see, but I have a board where ATmega8L doesnt want to work with 8MHz internal oscillator setting - the datasheet does not say its invalid setting, and I think I have used it before, but now this board only works at 4MHz or at 8MHz when the OSCCAL is written to lower value


Failure of 68HC908KX8 Monitor Mode

Started by Jack in comp.arch.embedded15 years ago 13 replies

Question: Is it possible to somehow disable the KX8's monitor mode by means of an application loaded into its flash memory? My setup as...

Question: Is it possible to somehow disable the KX8's monitor mode by means of an application loaded into its flash memory? My setup as follows: I built a MON08 circuit as per circuit on page 193 of 68HC908KX8.pdf. I used a 74HC04 inverter with 9.8304MHz crystal, and constructed the circuit on Veroboard. All voltage levels on the device measures OK, as well as the clock signal. I proceede...


8- to 16-bit Embedded System Upgrade

Started by karlbkeller in comp.arch.embedded15 years ago 19 replies

Hi! We're on a new project with the golden opportunity to upgrade a system from an 8-bit 8051 to a 16-bit MPU TBD. The application is pretty...

Hi! We're on a new project with the golden opportunity to upgrade a system from an 8-bit 8051 to a 16-bit MPU TBD. The application is pretty straightforward bit fiddling, with a clock interrupt and (USB?) link to a Windows PC. It's a basic interruptible single-tasking app, so it doesn't need a real time kernel. We want to move from assembler to C/C++ source, so compiler/library and debug t...


Another high end 16/32 bit uC, Wide Vcc, Wide Temp

Started by Jim Granville in comp.arch.embedded13 years ago 1 reply

I see Infineon release (early samples of) another iteration on their proven XC166 series, the XC2200 family : "most of the XC226x?s...

I see Infineon release (early samples of) another iteration on their proven XC166 series, the XC2200 family : "most of the XC226x?s instructions can be executed in just one machine cycle which requires 15ns at 66 MHz CPU clock. For example, shift and rotate instructions are always processed during one machine cycle independent of the number of bits to be shifted. Also multiplication ...


FPGA + Microcontroller - HELP

Started by LOC in comp.arch.embedded15 years ago 13 replies

Hi all, What is a device consisting of FPGA and microntroller suitable to following reqiurement: 1. my PCB board size is 2.5"x2.5" - small (so...

Hi all, What is a device consisting of FPGA and microntroller suitable to following reqiurement: 1. my PCB board size is 2.5"x2.5" - small (so I need a chip which has FPGA and Microcontroller ? ) 2. FPGA portion has minimum 28 JK FlipFlops, 28 shift registers, and the rest for IO and state machine, input clock 100 Mhz minimum. 3. microcontroller size has 2 serial ports, USB. Any advice wi...


Digital mic sharing on two MCUs

Started by John Speth in comp.arch.embedded2 years ago 7 replies

Hi there- I have a design inquiry that involves interfacing a pair of digital MEMs PDM microphones to two different MCU's (one for wake word...

Hi there- I have a design inquiry that involves interfacing a pair of digital MEMs PDM microphones to two different MCU's (one for wake word processing and another for speech processing after waking). Such a design would reasonably require two clock sources to the mic. Does anybody know what design strategies exist so that PDM mics can be shared among different downstream audio proc...


Secure Digital (SD) card initialization in SPI mode

Started by Anonymous in comp.arch.embedded15 years ago 3 replies

I'm attempting to interface to an SD card using an AT89S8252 MCU. I'm using an 74LS125 to convert between 5V and 3.3V. The hardware seems...

I'm attempting to interface to an SD card using an AT89S8252 MCU. I'm using an 74LS125 to convert between 5V and 3.3V. The hardware seems to be ok since I *do* get a response from the card but I'm having problems initializing the card in SPI mode. I am sending 96 clock cycles initially and then I send a CMD0. Everything I've read suggests that CMD0 should initially respond with 0x01 at w...


How to Un-Hang a DS RTC Chip Stuck in I2C La-La-Land ???

Started by B1ackwater in comp.arch.embedded11 years ago 8 replies

I've been working with a Real-Time-Clock chip, the DS-1337+, and noticed that if the final I2C read operation isn't accompanied by a 'no-ack'...

I've been working with a Real-Time-Clock chip, the DS-1337+, and noticed that if the final I2C read operation isn't accompanied by a 'no-ack' then I2C communications hang-up shortly thereafter. The PIC language I'm using (MikroPascal) does not have a proper "time-out" for I2C operations, so everything hangs until the watchdog finally kicks in, which is rather inelegant. The docs say the '...


Power/Clock Management

Started by eeboy in comp.arch.embedded10 years ago 1 reply

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


Where are device drivers with respect to HAL?

Started by janii in comp.arch.embedded6 years ago 1 reply

Where do device drivers fit with respect to Hardware Abstraction Layer(HAL)? For example, flash memory drivers or Real-Time Clock Drivers? Do...

Where do device drivers fit with respect to Hardware Abstraction Layer(HAL)? For example, flash memory drivers or Real-Time Clock Drivers? Do these device drivers have any interaction with HAL? --------------------------------------- Posted through http://www.EmbeddedRelated.com


Tech: Help Identifing a Motorola ASIC / FPGA

Started by Jim Knight in comp.arch.embedded14 years ago 1 reply

Looking to identify an "ASIC" and find information on same. Known info is as follows: Motorola 84pin PLCC Circa Mid-late 1980's 2 MHz...

Looking to identify an "ASIC" and find information on same. Known info is as follows: Motorola 84pin PLCC Circa Mid-late 1980's 2 MHz clock rate (in one application) Marking line1 - M (Duh!) Marking line2 - S38FC049PIO3 Marking line 3 - ZKZKAC9039 Speculative information: This module was programmed locally. Any guesses? I can post a picture if it would...


ADuC842 DAC glitches,forgot anything?

Started by blisca in comp.arch.embedded11 years ago

Hi I'm trying to do some practice with the 8bit uC AduC 842 When i generate a ramp by means of its DAC there are some glitches,in different...

Hi I'm trying to do some practice with the 8bit uC AduC 842 When i generate a ramp by means of its DAC there are some glitches,in different number and position each time a ramp is generated i vary the DAC out in this way int i,del; DACCON=0x0D; //Async,DAC0 on ,DAC1 off ADCCON1=0xAC;//Power up ADC/8 + 4 acq clock .. for(i=0;i > 8; DAC0L=i & 0x0FF; del=10;


Creating sound effects with PIC microcontroller

Started by Anonymous in comp.arch.embedded14 years ago 6 replies

I am developing a "smart" alarm clock. I need to determine how to I will generate the alarm sounds. The main requirement is the ability...

I am developing a "smart" alarm clock. I need to determine how to I will generate the alarm sounds. The main requirement is the ability to generate loud sounds and to vary the sound volume. One option is to use a PIC18Fxx processor (already part of the circuit) to generate the alarm tones and then feed them through an audio amplifier IC and small speaker. I could use a digital potentiometer t...