RPPSOC

Raspberry Pi System-on-a-Chip

Features

• PSOC part CY8C5267AXI-LP051
  • Core: ARM Cortex M3
  • Data Bus Width: 32 bit
  • Maximum Clock Frequency: 67 MHz
  • Program Memory Size: 128 kB
  • Data RAM Size: 32 kB
  • ADC Resolution: 12 bit
  • Data RAM Type: SRAM
  • Interface Type: I2C, USB
  • Number of ADC Channels: 1
  • Number of I/Os: 72 I/O
  • Number of Timers/Counters: 4 Timer
  • Program Memory Type: Flash
• Works on all Raspberry Pi cards with 40 pin GPIO (A+/B+/Pi2/Pi3/Zero)
• All 29 Raspberry Pi I/O lines are connected to the PSOC
• 3 of the lines are used for programming the PSSoC
• Configuration EEPROM
• Fuses on 3.3V and 5V power
• Two I/O connectors
• 14 + 16 = 30 I/O pins

PSoC Architecture

Headers / Connectors

• Card marking

H1 - Programming Header

• Can program the card via this connector
  • I use the KitProg part of CY8CKIT-059 with a 4-pin cable wired 1:1

• Note orientation of pin 1

H2 - EEPROM Write Enable

• Install jumper on header to program EEPROM from Raspberry Pi
  • Remove jumper to write Protect EEPROM

H3/H4 - I/O Voltage Select

• Select the I/O voltage on P3, P4 output connectors
  • 3.3 or 5V

J1 - Raspberry Pi GPIO Connector

P3 - I/O connector

• Header indicates PSoC port
• Schematic indicates PSoC pin number

P4 - I/O connector

• Header indicates PSoC port
• Schematic indicates PSoC pin number

Schematic

• RPPSOC Schematic

Factory Test Procedure

• Overview of test Procedures

1. Program Hat EEPROM on UUT
2. Test Card using Raspberry Pi and PSOC code
3. Load/Verify Shipping Program

Test Setup

• Unit Under Test (UUT)
• Raspberry Pi
• (2) LED-TEST-2 Cards attached to UUT J3, J4
• Cables set

Program Hat EEPROM on UUT

• Can program EEPROM using RPI_PSOC5 running RPI_PSOC5_Serial_01
• '2' to select RPPSOC
• 'W' to write EEPROM
• 'R' to read back EEPROM

Test Card using Raspberry Pi and PSOC code

• Download RPPSOC-FAT-Chain to RPPSOC using KitProg from PSoC Creator
• Description of the RPPSOC-FAT-Chain logic inside PSoC
  • Blinks LEDs attached to J3, J4 in a "circular" pattern
  • Loops back pins to Raspberry Pi
    • "Distant" pins are tested in pairs so pin shorts would be found

• On Raspberry Pi, run fastTests-RPPSOC.py

cd ~/RPPSOC/TestCodePi/
sudo python ./fastTests-RPP-SOC.py

• Verify all J3/J4 LEDs are displayed one at a time
• Loopback test repeats 100x
• Result should be

Passed 100 loop test

Load/Verify Shipping Program

• Program UUT with Shipment code RPPSOC-Blink2
• I/O pins (to Raspberry Pi and J3/J4) are not assigned so they don't conflict with external hardware or Host Raspberry Pi pins
• PSoC CPU code blinks on-board LED
  • Demonstrates that the CPU is running code
• When board is received by customer, the on-board LED should be blinking

Drivers/Example Code

• LB-RPPSOC GitHub Repo
• RPPSOC GitHub Repo
  • HSSP_Programmer - Code that programs PSoC from the Raspberry Pi (.o files)
  • EEPROM file - Data in the On-Board EEPROM

Programming PSoC from the Raspberry Pi

• Program the PSoC from the Raspberry Pi using Host Sourced Serial Programming
• Flow

Connections between Raspberry Pi and RPPSOC

Programmer	H1 pin	Python IO Pin	Pi connector pin	WiringPi IO Pin
RESET	H1-3	IO_22(Python)	Pi Pin 15	GPIO.3(WiringPi)
SWDCLK	H1-4	IO_23(Python)	Pi Pin 16	GPIO.4(WiringPi)
SWDIO	H1-6	IO_25(Python)	Pi Pin 17	GPIO.5(WiringPi)

SWD Timing for HSSP

Assembly Sheet

• RPPSOC Assembly Sheet