Document History

Date
Version
Author
Description of Revisions
27 May 2014
0.0
Prush
Initial Version
11 June, 2014
0.1
Upender
Added Command and response structures



Introduction

The host machine communicates with the application running on ZC702 board through UART channel. The GUI running on the target machine sends appropriate commands to the target application based on the user selection. For the GUI to successfully send command and receive a response a simple protocol is designed in the power demo setup. This Techtip explains this protocol that is used for command and response.

Block Diagram

This design example uses the UART protocol to communicate data between the GUI on host PC and Zynq-7000 AP SoC. The GUI example reference design will have the following components
  1. 1. On Windows Visual C# GUI
    1. a. Display the UART ports available on the host PC,
    2. b. Two text boxes
i. one for the input from the user and
ii. display the processed data from the Zynq-7000 AP SoC of the user input
  1. 2. Application running on Zynq-7000 AP SoC
    1. a. Receives the input string from user through the GUI
    2. b. Reserves the input string and sends back the reversed sting to the GUI
When user initiates the UART connection by selecting the corresponding UART port, GUI will enable the input text box for the user inputs. The user inputs will be transferred to the Zynq-7000 AP SoC and will be processed (reversed) and sends back the processed data back to the GUI through the UART port.

PowerDemo_Block_Diagram.png


Figure1: GUI example block diagram

Communication Protocol through UART


The command packet starts with “SOC” delimiter, short for Start Of Command and ends with “EOC” delimiter short for End of Command. The data between SOC and EOC is the actual command that the application will look for.
S
O
C
X
X
X
E
O
C


After executing the command received from the HOST, the UART application will send out the response in the following two formats. The format of the response when there is an error message is as mentioned below.
E
R
R
ANY
STR
ING

E
O
R

The format of the response after successful completion of the command is as mentioned below. This response packet will be send continuously at a rate of 2Hz, such that the GUI updates the values of voltage, current and power graph twice in a second. The response packet starts with a “SOR” delimiter short for Start Of Response and end with a “EOR” delimiter short for “End Of Response”.
S
O
R
nVoltage
nCurrent
nPower
Additional Data
E
O
R


The actual data that the GUI will use to update the graph is highlighted in yellow in the above table. The data includes Voltage, Current, Power for all 10 voltage rails and additional data which includes CPU frequency, DDR frequency, CPU utilization, Total Power consumed, MAX power consumed and temperature. Total Power is the total power consumed on all the rails at that instant and MAX power is the highest “Total Power” during the life of the application. The data in the response packet is with a precision of 2 decimal places.

Example Commands


1) Change CPU frequency to 222 MHz
S
O
C
1
1
x
E
O
C



2) Change CPU frequency to 333 MHz

S
O
C
1
2
x
E
O
C


3) Change CPU frequency to 667 MHz

S
O
C
1
3
x
E
O
C


1) Change CPU load to idle (no load)
S
O
C
1
x
1
E
O
C



2) Run Spec2000 load on one core

S
O
C
1
x
2
E
O
C


1) Run Spec2000 load on two cores

S
O
C
1
x
3
E
O
C


Example Response


SOR:1.00:255.00:255.47:1.00:274.69:274.55:1.80:15.31:27.47:1.80:84.06:150.90:2.5 1:12.19:30.59:1.50:417.19:625.09:1.81:6.88:12.40:1.00:8.75:8.73:3.29:357.50:1173 .65:2.50:7.81:19.52:666.00:533.00:0.00:0.00:2578.36:2578.36:25.17:EOR

Power Demo GUI input commands


PowerDemo GUI Ribbon.png
Figure 2 : Power demo GUI Command Input


Power Demo GUI inputs commands and possible values for each parameter in command.
The list is not limited to the below table. There will be many combinations of commands with different values shown in the table below



PS Configuration
PL Configuration
S/No
COMMANDS
PS FREQUENCY INDEX
PS LOAD INDEX
PL FREQUENCY INDEX
PL UTILIZATION INDEX
ACCUMULATOR
LFSR
TOGGLE FLIP-FLOP









1
SOC1111111EOC
1(667MHz)
1
1
1
UN CHECKED
UN CHECKED
UN CHECKED
2
SOC1211111EOC
2(333MHz)
1
1
1
UN CHECKED
UN CHECKED
UN CHECKED
3
SOC1311111EOC
3(222MHz)
1(CPU_IDLE)
1
1
UN CHECKED
UN CHECKED
UN CHECKED
4
SOC1121111EOC
1
2(Spec 2000:1 Load)
1
1
UN CHECKED
UN CHECKED
UN CHECKED
5
SOC1131111EOC
1
3(Spec 2000:2 Load)
1
1
UN CHECKED
UN CHECKED
UN CHECKED
6
SOC114111EOC
1
4(STANDBY)
1(0MHz)
1
UN CHECKED
UN CHECKED
UN CHECKED
7
SOC1112111EOC
1
1
2(50MHz)
1
UN CHECKED
UN CHECKED
UN CHECKED
8
SOC1113111EOC
1
1
3(100MHz)
1
UN CHECKED
UN CHECKED
UN CHECKED
9
SOC1114111EOC
1
1
4(150MHz)
1
UN CHECKED
UN CHECKED
UN CHECKED
10
SOC1115111EOC
1
1
5(200MHz)
1(0%)
UN CHECKED
UN CHECKED
UN CHECKED
11
SOC1111211EOC
1
1
1
2(25%)
UN CHECKED
UN CHECKED
UN CHECKED
12
SOC1111311EOC
1
1
1
3(50%)
UN CHECKED
UN CHECKED
UN CHECKED
13
SOC1111411EOC
1
1
1
4(75%)
UN CHECKED
UN CHECKED
UN CHECKED
14
SOC1111511EOC
1
1
1
5(100%)
UN CHECKED
UN CHECKED
UN CHECKED
15
SOC1111121EOC
1
1
1
1
UN CHECKED
UN CHECKED
CHECKED
16
SOC1111131EOC
1
1
1
1
UN CHECKED
CHECKED
UN CHECKED
17
SOC1111141EOC
1
1
1
1
UN CHECKED
CHECKED
CHECKED
18
SOC1111151EOC
1
1
1
1
CHECKED
UN CHECKED
UN CHECKED
19
SOC1111161EOC
1
1
1
1
CHECKED
UN CHECKED
CHECKED
20
SOC1111171EOC
1
1
1
1
CHECKED
CHECKED
UN CHECKED
21
SOC1111181EOC
1
1
1
1
CHECKED
CHECKED
CHECKED

Power Demo GUI output response structure and details


Response values from the target are separated with colon as shown below.
C# program running on host PC will interpret the values and updates the GUI graphs and corresponding text boxes
POwer Demo Code.PNG
Code Snippet for output response



The response string from the Zynq target will have 37 status values.Below is the description about the each response value.
Response Number
Description
R1
Rail VccInt: Voltage
R2
Rail VccInt: Current
R3
Rail VccInt: Power
R4
Rail VccPInt: Voltage
R5
Rail VccPInt: Current
R6
Rail VccPInt: Power
R7
Rail VccAux: Voltage
R8
Rail VccAux: Current
R9
Rail VccAux: Power
R10
Rail VccPAux: Voltage
R11
Rail VccPAux: Current
R12
Rail VccPAux: Power
R13
Rail Vadj: Voltage
R14
Rail Vadj: Current
R15
Rail Vadj: Power
R16
Rail VcoDDR: Voltage
R17
Rail VcoDDR: Current
R18
Rail VcoDDR: Power
R19
Rail VccMIO: Voltage
R20
Rail VccMIO: Current
R21
Rail VccMIO: Power
R22
Rail VccBRAM: Voltage
R23
Rail VccBRAM: Current
R24
Rail VccBRAM: Power
R25
Rail Vcc3.3V: Voltage
R25
Rail Vcc3.3V: Current
R27
Rail Vcc3.3V: Power
R28
Rail Vcc2.5V: Voltage
R29
Rail Vcc2.5V: Current
R30
Rail Vcc2.5V: Power
R31
CPU Frequncy
R32
DDR Frequncy
R33
CPU0 Utilization
R34
CPU1 Utilization
R35
Total Power
R36
Max Power
R37
Zynq Die Temparature