Specifications

Chapter 2 – Hardware Resources
30 PL 3120/PL 3150/PL 3170 Power Line Smart Transceiver Data Boo
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• I/O pin initialization step — Initialize I/O pins based on application definition. Prior to this point, I/O pins are
high impedance.
• State wait II — Wait for the device to leave the unconfigured or hard-offline state. If waiting was required, a
flag is set to indicate that the device should come up offline.
• Parallel I/O synchronization — Devices using parallel I/O attempt to execute the master/slave synchroni-
zation protocol at this point.
• Reset task — Execute the application reset task (when (reset){ }).
• If the offline flag was set, go offline and execute the offline task (when(offline){}). If the BIST flag
indicated a failure, then the SERVICE~ pin is turned on and the offline task is executed. Otherwise, the sched-
uler starts its normal task scheduling loop.
The amount of time required to perform these steps depends on many factors, including: PL Smart Transceiver model;
input clock rate; whether or not the device performs a boot process; whether the device is applicationless, configured, or
unconfigured; amount of off-chip RAM; whether the off-chip RAM is tested or simply cleared; the number of buffers
allocated; and application initialization. Tables 2.8 and 2.9 summarize the number of input clock cycles (XIN) required
for each of these steps for the PL 3120 and the PL 3150 Smart Transceivers. The times are approximate and are given as
functions of the most significant application variables.
Table 2.8 PL 3120 Smart Transceiver Reset Sequence Time
Step Number of XIN Cycles Notes
Stack Initialization and BIST 386,000
SERVICE~ Pin Initialization 1000
State Initialization 250 (for no boot)
2,275,000 (for boot)
Off-Chip RAM Initialization 0
Random Number Seed Calculation 0 1
System RAM Set-up 21,000 + 600*B 2
Communication Port Initialization 0 1
Checksum Initialization 3400 + 175*M 3
One-Second Timer Initialization 6100
Scheduler Initialization ≥ 7400 4
Notes:
1) These tasks run in parallel with other tasks.
2) B is the number of application and/or network buffers allocated.
3) M is the number of bytes to be checksummed.
4) Assumes a trivial initialization task, no reset task and the configured state.
For example, the timing of each of these steps is shown for a PL 3120 Smart Transceiver application with the following
parameters:
• 10MHz input clock
• Crystal oscillator
• No boot required, at least 10 application and/or network buffers
• 500 bytes of EEPROM checksummed.