Search:

It works fine at 10MHz. So I don't think that will introduce problem. the memory writing speed goes up a lot! I will try his codes tomorrow..also looks interesting. anyway thanks for u guys' help!

Just follow up with the my test. It is interesting that because I didn't specify the SCK's direction which killed the engine for SPI. Right now it is working. A little tricky problem, and anyway I...

As I found out the reads are all zeros, I use os-scope to track the signals and found out that there is totally no signals out in SCK, therefore no SDI because the master is not generating clocks....

Still with no results... The reads I get for the four variables are all zeros. I mean X1 to X4.It seems like there are response from SDO. But never get anything in SDI from the os-scope. It is...

Thanks Paul:-)
Really it is not quite easy. Last time it took me several days to find out the problem with SHIFTIN SHIFTOUT. I am sure the chip is working with those commands. But you know it is too...

Actually I could use SHIFTIN and SHIFTOUT for accessing the F-RAM memory, as you told, it is a "comedy" wiring error, it seems like totally reversed. But for hardware SPI, I think the MISO,MOSI...

Thanks Paul for your shared codes!!! It is great.
I did the same test, but used PIC16LF877(3.0V) and FM25V10(3.0V,1Mbit). I think the communication is the same, only with some minor modifications. I...

Hi Paul: I am actually trying to figure out the hardware SPI module for F-RAM. So can you share your codes for that part? I appreciate it very much!!!

Vinson

I am trying to inteface SPI-FRAM with PIC16F877A for a long time. I am sure the hardware connection is correct. Just got some wired results....See anybody can tell me what's the reason and is there...

I tested on a separate circuit with a 3.0Voltage supply using PIC16LF877A and this Ram chip. There was some results come out, but not correct....
For example I wrote 100 into the first 100 location...

Thanks Darrel I will test separately and see if I could get it through

Yes, I am using the LAB-X1 board for this test.
I provided a 3.3V power supply for the SRAM. But for the SI SO SCK pins I didn't modify them to 3.3V,just connect them directly to the SRAM's pins.

The data I read out for BI is always 255...

I am trying to connect the SPI SRAM 23K256 with PIC16LF877a, double checked everything about the connection and the codes,still no result...
The following is the test code I am using..I appreciate...

Thanks Norm the your suggestions and the sample codes. IN the manual it sounds like 1~256 is a flexiable range that can be written. Any way I will try it out later.

Sounds good. The EEPROMs require a 5ms wirting circle typically from Microchips. While it can be reduced to about 3ms as I tried.

Yes, Alian is right and hardware is the core constrain. I did some revise for the previous codes like reading the accelerometer(six bytes register for three axes) in one I2C read, and the same...

Thanks a lot!
It has been long since my visit of this site here. Year, pretty much the chips you provided could solve the speed issue, also with a smaller package!
I

First, thanks a lot for your reply. While, it does work if I reduce the I2CRead commands. So, do you think it could be better, if I use assembly codes to perform the I2CReads and I2Cwrites? What am...

I've been trying to build a vibration sensor with the PIC16F877. The sensor essentially has an tri-axis digital accelerometer using I2C or SPI, an serial EEPROM. The program works for fine for...

I am trying to use 24AA1025 for data storage.
Word address <ADD> and word variable <DA>. I am trying to save DA into the EEPROM memory at a bandwidth of 50.
I read through all the datasheets and...