#!/usr/bin/env python3 # BSD 3-Clause License # # Copyright (c) 2021, akuker # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # 1. Redistributions of source code must retain the above copyright notice, this # list of conditions and the following disclaimer. # # 2. Redistributions in binary form must reproduce the above copyright notice, # this list of conditions and the following disclaimer in the documentation # and/or other materials provided with the distribution. # # 3. Neither the name of the copyright holder nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE # DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. import RPi.GPIO as gpio import time pin_settle_delay = 0.01 err_count = 0 # Define constants for each of the SCSI signals, based upon their # raspberry pi pin number (since we're using BOARD mode of RPi.GPIO) scsi_d0_gpio = 19 scsi_d1_gpio = 23 scsi_d2_gpio = 32 scsi_d3_gpio = 33 scsi_d4_gpio = 8 scsi_d5_gpio = 10 scsi_d6_gpio = 36 scsi_d7_gpio = 11 scsi_dp_gpio = 12 scsi_atn_gpio = 35 scsi_rst_gpio = 38 scsi_ack_gpio = 40 scsi_req_gpio = 15 scsi_msg_gpio = 16 scsi_cd_gpio = 18 scsi_io_gpio = 22 scsi_bsy_gpio = 37 scsi_sel_gpio = 13 # Pin numbers of the direction controllers of the PiSCSI board piscsi_ind_gpio = 31 piscsi_tad_gpio = 26 piscsi_dtd_gpio = 24 piscsi_none = -1 # Matrix showing all of the SCSI signals, along what signal they're looped back to. # dir_ctrl indicates which direction control pin is associated with that output gpio_map = [ { "gpio_num": scsi_d0_gpio, "attached_to": scsi_ack_gpio, "dir_ctrl": piscsi_dtd_gpio, }, { "gpio_num": scsi_d1_gpio, "attached_to": scsi_sel_gpio, "dir_ctrl": piscsi_dtd_gpio, }, { "gpio_num": scsi_d2_gpio, "attached_to": scsi_atn_gpio, "dir_ctrl": piscsi_dtd_gpio, }, { "gpio_num": scsi_d3_gpio, "attached_to": scsi_rst_gpio, "dir_ctrl": piscsi_dtd_gpio, }, { "gpio_num": scsi_d4_gpio, "attached_to": scsi_cd_gpio, "dir_ctrl": piscsi_dtd_gpio, }, { "gpio_num": scsi_d5_gpio, "attached_to": scsi_io_gpio, "dir_ctrl": piscsi_dtd_gpio, }, { "gpio_num": scsi_d6_gpio, "attached_to": scsi_msg_gpio, "dir_ctrl": piscsi_dtd_gpio, }, { "gpio_num": scsi_d7_gpio, "attached_to": scsi_req_gpio, "dir_ctrl": piscsi_dtd_gpio, }, { "gpio_num": scsi_dp_gpio, "attached_to": scsi_bsy_gpio, "dir_ctrl": piscsi_dtd_gpio, }, { "gpio_num": scsi_atn_gpio, "attached_to": scsi_d2_gpio, "dir_ctrl": piscsi_ind_gpio, }, { "gpio_num": scsi_rst_gpio, "attached_to": scsi_d3_gpio, "dir_ctrl": piscsi_ind_gpio, }, { "gpio_num": scsi_ack_gpio, "attached_to": scsi_d0_gpio, "dir_ctrl": piscsi_ind_gpio, }, { "gpio_num": scsi_req_gpio, "attached_to": scsi_d7_gpio, "dir_ctrl": piscsi_tad_gpio, }, { "gpio_num": scsi_msg_gpio, "attached_to": scsi_d6_gpio, "dir_ctrl": piscsi_tad_gpio, }, { "gpio_num": scsi_cd_gpio, "attached_to": scsi_d4_gpio, "dir_ctrl": piscsi_tad_gpio, }, { "gpio_num": scsi_io_gpio, "attached_to": scsi_d5_gpio, "dir_ctrl": piscsi_tad_gpio, }, { "gpio_num": scsi_bsy_gpio, "attached_to": scsi_dp_gpio, "dir_ctrl": piscsi_tad_gpio, }, { "gpio_num": scsi_sel_gpio, "attached_to": scsi_d1_gpio, "dir_ctrl": piscsi_ind_gpio, }, ] # List of all of the SCSI signals that is also a dictionary to their human readable name scsi_signals = { scsi_d0_gpio: "D0", scsi_d1_gpio: "D1", scsi_d2_gpio: "D2", scsi_d3_gpio: "D3", scsi_d4_gpio: "D4", scsi_d5_gpio: "D5", scsi_d6_gpio: "D6", scsi_d7_gpio: "D7", scsi_dp_gpio: "DP", scsi_atn_gpio: "ATN", scsi_rst_gpio: "RST", scsi_ack_gpio: "ACK", scsi_req_gpio: "REQ", scsi_msg_gpio: "MSG", scsi_cd_gpio: "CD", scsi_io_gpio: "IO", scsi_bsy_gpio: "BSY", scsi_sel_gpio: "SEL", } # Debug function that just dumps the status of all of the scsi signals to the console def print_all(): for cur_gpio in gpio_map: print( cur_gpio["name"] + "=" + str(gpio.input(cur_gpio["gpio_num"])) + " ", end="", flush=True, ) print("") # Set transceivers IC1 and IC2 to OUTPUT def set_dtd_out(): gpio.output(piscsi_dtd_gpio, gpio.LOW) # Set transceivers IC1 and IC2 to INPUT def set_dtd_in(): gpio.output(piscsi_dtd_gpio, gpio.HIGH) # Set transceiver IC4 to OUTPUT def set_ind_out(): gpio.output(piscsi_ind_gpio, gpio.HIGH) # Set transceiver IC4 to INPUT def set_ind_in(): gpio.output(piscsi_ind_gpio, gpio.LOW) # Set transceiver IC3 to OUTPUT def set_tad_out(): gpio.output(piscsi_tad_gpio, gpio.HIGH) # Set transceiver IC3 to INPUT def set_tad_in(): gpio.output(piscsi_tad_gpio, gpio.LOW) # Set the specified transciever to an OUTPUT. All of the other transceivers # will be set to inputs. If a non-existent direction gpio is specified, this # will set all of the transceivers to inputs. def set_output_channel(out_gpio): if out_gpio == piscsi_tad_gpio: set_tad_out() else: set_tad_in() if out_gpio == piscsi_dtd_gpio: set_dtd_out() else: set_dtd_in() if out_gpio == piscsi_ind_gpio: set_ind_out() else: set_ind_in() # Main test procedure. This will execute for each of the SCSI pins to make sure its connected # properly. def test_gpio_pin(gpio_rec): global err_count set_output_channel(gpio_rec["dir_ctrl"]) ############################################ # set the test gpio low gpio.output(gpio_rec["gpio_num"], gpio.LOW) time.sleep(pin_settle_delay) # loop through all of the gpios for cur_gpio in scsi_signals: # all of the gpios should be high except for the test gpio and the connected gpio cur_val = gpio.input(cur_gpio) if cur_gpio == gpio_rec["gpio_num"]: if cur_val != gpio.LOW: print( "Error: Test commanded GPIO " + scsi_signals[gpio_rec["gpio_num"]] + " to be low, but it did not respond" ) err_count = err_count + 1 elif cur_gpio == gpio_rec["attached_to"]: if cur_val != gpio.LOW: print( "Error: GPIO " + scsi_signals[gpio_rec["gpio_num"]] + " should drive " + scsi_signals[gpio_rec["attached_to"]] + " low, but did not" ) err_count = err_count + 1 else: if cur_val != gpio.HIGH: print( "Error: GPIO " + scsi_signals[gpio_rec["gpio_num"]] + " incorrectly pulled " + scsi_signals[cur_gpio] + " LOW, when it shouldn't have" ) err_count = err_count + 1 ############################################ # set the transceivers to input set_output_channel(piscsi_none) time.sleep(pin_settle_delay) # loop through all of the gpios for cur_gpio in scsi_signals: # all of the gpios should be high except for the test gpio cur_val = gpio.input(cur_gpio) if cur_gpio == gpio_rec["gpio_num"]: if cur_val != gpio.LOW: print( "Error: Test commanded GPIO " + scsi_signals[gpio_rec["gpio_num"]] + " to be low, but it did not respond" ) err_count = err_count + 1 else: if cur_val != gpio.HIGH: print( "Error: GPIO " + scsi_signals[gpio_rec["gpio_num"]] + " incorrectly pulled " + scsi_signals[cur_gpio] + " LOW, when it shouldn't have" ) err_count = err_count + 1 # Set the transceiver back to output set_output_channel(gpio_rec["dir_ctrl"]) ############################################# # set the test gpio high gpio.output(gpio_rec["gpio_num"], gpio.HIGH) time.sleep(pin_settle_delay) # loop through all of the gpios for cur_gpio in scsi_signals: # all of the gpios should be high cur_val = gpio.input(cur_gpio) if cur_gpio == gpio_rec["gpio_num"]: if cur_val != gpio.HIGH: print( "Error: Test commanded GPIO " + scsi_signals[gpio_rec["gpio_num"]] + " to be high, but it did not respond" ) err_count = err_count + 1 else: if cur_val != gpio.HIGH: print( "Error: GPIO " + scsi_signals[gpio_rec["gpio_num"]] + " incorrectly pulled " + scsi_signals[cur_gpio] + " LOW, when it shouldn't have" ) err_count = err_count + 1 # Initialize the GPIO library, set all of the gpios associated with SCSI signals to outputs and set # all of the direction control gpios to outputs def setup(): gpio.setmode(gpio.BOARD) gpio.setwarnings(False) for cur_gpio in gpio_map: gpio.setup(cur_gpio["gpio_num"], gpio.OUT, initial=gpio.HIGH) # Setup direction control gpio.setup(piscsi_ind_gpio, gpio.OUT) gpio.setup(piscsi_tad_gpio, gpio.OUT) gpio.setup(piscsi_dtd_gpio, gpio.OUT) # Main functions for running the actual test. if __name__ == "__main__": # setup the GPIOs setup() # Test each SCSI signal in the gpio_map for cur_gpio in gpio_map: test_gpio_pin(cur_gpio) # Print the test results if err_count == 0: print("-------- Test PASSED --------") else: print("!!!!!!!! Test FAILED !!!!!!!!") print("Total errors: " + str(err_count)) gpio.cleanup()