Data Calculations

Hi everyone,

I am trying to interface USBee=91s Experimenter board,

/usbeeex2.html to a CPLD. The USB device outputs 8 bit of data on its eight parallel data lines at each falling edge of its CLOCK. The Clock frequency is

24 MHz.

The CPLD writes this data into the Dual Port RAM,

This RAM has 19 bit of address bus and 18 bit data bus. So, it has

512 k word of memory locations and each memory location is 18 bit wide. Am I right? So, it has 524 k x 18 =3D 9.4 M bits, Am I right?

I only need 14 bit of data. So, I guess 524 k x 14 =3D 7.3 M bits. Am I right? So, CPLD writes first eight bit of data to the RAM on the first falling edge of the CLOCK and then the 5 bit of data on the second falling edge of the CLOCK.

I need to calculate in how much time CPLD writes the full RAM with data.

So, I guess it takes

41.6nsec to write a byte and 83.2 nsec to write two bytes or write one RAM location. 43.5 msec to write 524 k RAM locations.

Am I right about this?