Hi,
I am looking for a way to use external EEPROM with an 18F series chip. Does anyone know if
a)there is an 80 pin chip that actually has EEPROM, or
b)if there is a way to communicate to an external EEPROM chip?
This is extremely annoying, as I need all the I/O's of the 18F series, but also with EEPROM. I understand that a few pins will need to go to EEPROM, and that is fine.
Any Help?
Thanks,
Conor(15)
Need help...
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Re: Need help...
Hello Conor,
There are a small number of 80-pin, 18F serier PICs that contain EEPROM. Exmples are: 18F8520/8527/8622/8627/8722. Each provides 1K of EEPROM. If this is insufficient, or the devices are unsuitable for other reasons, external EEPROMs can be added via the I2C or SPI busses. SPI provided a higher data transfer but requies up to 4 port pins. The I2C bus is slower but requires only 2 port pins.
Both busses use internal hardware that is only available on specific port pins. Flowcode also provides a software implementation of the I2C bus that can be allocated to any available port pins.
There are a small number of 80-pin, 18F serier PICs that contain EEPROM. Exmples are: 18F8520/8527/8622/8627/8722. Each provides 1K of EEPROM. If this is insufficient, or the devices are unsuitable for other reasons, external EEPROMs can be added via the I2C or SPI busses. SPI provided a higher data transfer but requies up to 4 port pins. The I2C bus is slower but requires only 2 port pins.
Both busses use internal hardware that is only available on specific port pins. Flowcode also provides a software implementation of the I2C bus that can be allocated to any available port pins.