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opentag:radios:cc11xx

CC11xx Radio Core

The TI CC11xx radio core is used in many devices, including the CC1101, CC1110, CC1111, CC1120, CC1121, and also the CC430 family of SoCs. In most regards, these chips are all the same, however each model has its own special features. All CC11xx devices are sub 1GHz RF transceivers that can support OpenTag and DASH7 Mode 2 quite well.

Common Family Attributes

All CC11xx devices have a fast-starting Fractional-N PLL that enables them to very quickly go from sleep to active RX/TX. They also have a fast-settling preamble detector that allows an additional parameter, PQI (Preamble Quality Indicator), to be used to prevent random sync word acquisition. They support a built-in packet data format of fixed-length, infinite-length, or variable-length packets (variable-length has a length byte at the front of the frame). Most of the devices also support DASH7's PN9 encoding and FEC encoding in HW, but they do not support DASH7's CRC spec. On the downside, they are not the lowest power of all devices (typ 15mA RX, 17mA TX), and they do not have the best sensitivity. However, it is known that sensitivity can be increased quite a bit by careful configuration of the internal front-end register settings (reports say 17dB better than default).

CC1101

The CC1101 is a refinement of the earlier CC1100.

Feature Notes
Data Interface SPI bus
IRQ Interface 3x configurable lines
FIFO 64 bytes RX, 64 bytes TX
Spectrum 310, 433, 866, 915 MHz bands
Modulations ASK, (G)FSK, MSK
Max Data Rate 250 kbps (practical)
PN9 Yes
FEC Yes
CRC No (not DASH7 spec)
Carrier Sense Yes, ~6dB precision
Clear Channel Yes, ~6dB precision

CC1110/1111

The CC1100 and CC1111 are identical to the CC1101, except that they also integrate an 8051 MCU. The CC1111 also includes a built-in USB device interface.

CC1120/1121

The CC1120 and 1121 are higher-performance variants of the CC1101. They have greater sensitivity and even faster turn-on and signal acquisition time. It is reported that they can acquire a preamble so quickly that they can be put into a 1/4 RX listening duty cycle to save extra power. The 1120 is more sensitive than the 1121 is, but the 1121 is lower cost.

Feature Notes
Data Interface SPI bus
IRQ Interface 3x configurable lines
FIFO 128 bytes RX, 128 bytes TX
Spectrum 167, 310, 433, 866, 915 MHz bands
Modulations ASK, (G)FSK, 4-(G)FSK, MSK, Analog FM
Max Data Rate 200 kbps
PN9 Yes
FEC Yes
CRC No (not DASH7 spec)
Carrier Sense Yes, ~6dB precision
Clear Channel Yes, ~6dB precision

CC430

The CC430 is an MSP430F5 MCU put onto the same die as a CC1101 radio core. However, there are some notable differences. First, the CC430 does not have the CC1101 FEC, but it does have a much better radio core timer and a much better method for doing Carrier Sense and Clear Channel Assessment – namely, it has an “RSSI Valid” interrupt source that offers vastly superior performance in terms of speed AND precision. The CC430 MCU also contains a HW peripheral that is capable of decoding the DASH7 CRC. Second, the addition of the highly integrated MCU allows the CC430 to manipulate the radio core registers while it is asleep, saving a bunch of power.

Generally speaking, the CC430 is preferable to any other CC11xx devices except possible the 1120/1121. OpenTag implementations for the CC11xx radio are probably best when using the CC430, either as a fully integrated system (typical) or a highly abstracted baseband processor.

Feature Notes
Data Interface Direct Register Access
IRQ Interface 3x configurable lines + 16 registered interrupts
FIFO 64 bytes RX, 64 bytes TX
Spectrum 310, 433, 866, 915 MHz bands
Modulations ASK, (G)FSK, MSK
Max Data Rate 250 kbps (practical)
PN9 Yes
FEC No
CRC Yes
Carrier Sense Yes, ~1dB precision
Clear Channel Yes, ~1dB precision
opentag/radios/cc11xx.txt · Last modified: 2012/03/06 18:51 by jpnorair