What's One-Wait-State On-Chip ROM mean in TI?

Telling us which of the gazzilion TI processors you're talking about would be helpful. Usually if they mean flash they say "flash", though.

Some memories are faster than others. When the memory is slower than the processor's cycle time, the processor must wait one or more clock cycles for data from it after the address has been asserted. Each such cycle is called a wait state.

ROM = read-only memory. Read-only means no writes.

Jerry

From that little bit of information I couldn't tell you. One Wait State ROM means the CPU/CORE has to wait one bus cycle when accessing the ROM because it (the ROM) is slower than the CPU is. ROM is a pretty generic term these days and if it is REALLY ROM then once it is programmed/masked it is over. Now EEPROM, EPROM, FLASH can be erased and used again. I'm sure the datasheet has all of the information you need. You just need to read it completely.

Jim

Hi all,

Thank you for your help :-)

I mean the 320VC55x series(320VC5509). Can I program the ROM or let TI do that? And if TI do that, how about the cost?

Any suggestions will be appreciated!

Best regards, Davy

No, as Jerry Avins said, it means that there is an extra cycle (wait state) between the address and read portion of the access cycle.

Hi Jasen,

Thank you :-)

I have one more question. If I have no on-chip Flash on TI's DSP, how to protect my code? For everyone can copy my code from Flash and produce another product?

All the best, Davy

one wait state means it's half as fast as the cpu, if it was user programmable they'd probably call it PROM,EPROM,FLASH or EEPROM.

Bye. Jasen

yes they can.

one option is to set the circuit in resin to make it hard to access the flash another is to use a DSP with built in read-protectable PROM etc. if you intend to produce large quuantities (eg ten thousand) TI can make them already programmed (so called mask ROM)

Bye. Jasen