EM260-RTR Ember, EM260-RTR Datasheet - Page 25

• Manufacturer Part Number: EM260-RTR
• Description: IC ZIGBEE SYSTEM-ON-CHIP 40-QFN
• Manufacturer: Ember

Specifications of EM260-RTR

• Frequency: 2.4GHz
• Data Rate - Maximum: 250kbps
• Modulation Or Protocol: 802.15.4
• Applications: ZigBee™
• Power - Output: -32dBm ~ 3dBm
• Sensitivity: -97dBm
• Voltage - Supply: 2.1 V ~ 3.6 V
• Current - Receiving: 30mA
• Current - Transmitting: 34mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 40-QFN
• For Use With: 636-1009 - PROGRAMMER USB FLASH EM250/260
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -
• Other names: 636-1007-2; EM260-RTR

5.2.6
Waking up the EM260 involves a simple handshaking routine as illustrated in Figure 5. This handshaking insures
that the Host will wait until the EM260 is fully awake and ready to accept commands from the Host. If the
EM260 is already awake when the handshake is performed (such as when the Host resets and the EM260 is
already operating), the handshake will proceed as described below with no ill effects.
Waking the EM260 involves the following steps:
1. Host asserts nWAKE.
2. EM260 interrupts on nWAKE and exits sleep.
3. EM260 performs all operations it needs to and will not respond until it is ready to accept commands.
4. EM260 asserts nHOST_INT within 10ms of nWAKE asserting. If the EM260 does not assert nHOST_INT within
5. Host detects nHOST_INT assertion. Since the assertion of nHOST_INT indicates the EM260 can accept SPI
6. Host deasserts nWAKE after detecting nHOST_INT assertion.
7. EM260 will deassert nHOST_INT within 25µs of nWAKE deasserting.
8. After 25µs, any change on nHOST_INT will be an indication of a normal asynchronous (callback) event.
5.2.7
If two or more different error conditions occur back to back, only the first error condition will be reported to
the Host (if it is possible to report the error). The following are error conditions that might occur with the
EM260.
10ms of nWAKE, it is valid for the Host to consider the EM260 unresponsive and to reset the EM260.
transactions, the Host does not need to hold Slave Select high for the normally required minimum 1ms of
inter-command spacing.
Oversized EZSP Frame: If the transaction includes an EZSP Frame, the Length Byte cannot be a value
greater than 125. If the EM260 detects a length byte greater than 125, it will drop the incoming Command
and abort the entire transaction. The EM260 will then assert nHOST_INT after Slave Select returns to Idle
to inform the Host through an error code in the Response section what has happened. Not only is the
Command in the problematic transaction dropped by the EM260, but the next Command is also dropped,
because it is responded to with the Oversized EZSP Frame Error Response.
Aborted Transaction: An aborted transaction is any transaction where Slave Select returns to Idle prema-
turely and the SPI Protocol dropped the transaction. The most common reason for Slave Select returning to
Idle prematurely is the Host unexpectedly resetting. If a transaction is aborted, the EM260 will assert
nHOST_INT to inform the Host through an error code in the Response section what has happened. When a
transaction is aborted, not only does the Command in the problematic transaction get dropped by the
EM260, but the next Command also gets dropped since it is responded to with the Aborted Transaction Er-
ror Response.
Waking the EM260 from Sleep
Error Conditions
HOST _ INT
WAKE
Figure 5. EM260 Wake Sequence
120-1003-000D
EM260
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