Introduction¶

The device power supply is divided into two parts.

Analog¶

+5 V, −5 V supply
Over-current protection
Automatically enabled when AIN/AOUT is enabled.
Automatically disabled on over-current
Enable/disable from Computer
Poll Status from Computer
“±5V” LED for quick feedback
Shared with on-board OPAMP’s

Digital¶

+3.3 V Supply
Over-current protection
Automatically enabled when SPI/I2C enabled.
Automatically disabled on over-current
Activate/Deactivate from Computer
Poll activate status from Computer
“+3.3V” LED for quick feedback

Usage¶

LED¶

The power supplies has respective LED for quick feedback.

OFF	Power supply is inactive
ON	Power supply is active
BLINK	Over-current and power supply is inactive

Short-circuit protection¶

When The user accidentally connect power pins to GND or opposite polarity.
In case, over-current occurs and the user will know that something is wrong.
for quick feedback, the respective LED will BLINK.

High Level Program¶

In [ ]:

#
# box-v5 Power Supply
# Author: Kuldeep Singh Dhaka <kuldeepdhaka9@gmail.com>
# Licence: GPLv3 or later
#

import box0

# python2 raw_input and python3 input
try: input = raw_input
except: pass

dev = box0.usb.open_supported()

print("Welcome! please enter a command:")
print("  b - [both] digital supply enable and analog supply enable")
print("  a - [analog] analog supply enable and digital supply disable")
print("  d - [digital] digital supply enable and analog supply disable")
print("  n - [none] digital supply disable and analog supply disable")
print("  s - [status] both suppy status")
print("  e - [exit] exit the program")

#turn both supply off
dev.ps_en_set(dev.PS_ANALOG | dev.PS_DIGITAL, 0)

try:
    while True:
        c = input("> ")
        if c == "b":
            dev.ps_en_set(dev.PS_ANALOG | dev.PS_DIGITAL, dev.PS_ANALOG | dev.PS_DIGITAL)
        elif c == "a":
            dev.ps_en_set(dev.PS_ANALOG, dev.PS_ANALOG)
        elif c == "d":
            dev.ps_en_set(dev.PS_DIGITAL, dev.PS_DIGITAL)
        elif c == "n":
            dev.ps_en_set(dev.PS_ANALOG | dev.PS_DIGITAL, 0)
        elif c == "s":
            mask = dev.ps_en_get()
            print("Analog: " + ("Enabled" if mask & dev.PS_ANALOG else "Disabled"))
            print("Digital: " + ("Enabled" if mask & dev.PS_DIGITAL else "Disabled"))
        elif c == "e":
            break;
        else:
            print("unknown command: " + c)
except KeyboardInterrupt: pass

#turn all supply off
dev.ps_en_set(dev.PS_ANALOG | dev.PS_DIGITAL, 0)

#close device
del dev

Low level Protocol Program¶

Constants¶

Name	Value
PS_EN_GET	201
PS_EN_SET	202
PS_OC_GET	203
PS_OC_ACK	204

Read enable value¶

bmRequestType	Host ← Device, Device, Vendor
bRequest	PS_EN_GET
wValue	0x0000
wIndex	0x0000
wLength	0x0001
Data	BIT0 = Analog, BIT1 = Digital

Note: BITx = 0, supply is off.
Note: BITx = 1, supply is on.

Write enable value¶

bmRequestType	Host → Device, Device, Vendor
bRequest	PS_EN_SET
wValue	HIGH8(mask) LOW8(value)
wIndex	0x0000
wLength	0x0000
Data	None

Note: In mask: BITx = 0, then crossponding value BITx is considered valid.
Note: In value: BIT0 = Analog, BIT1 = Digital. BITx = 0 mean off, and BITx = 1 means "on".

Read over-current value¶

bmRequestType	Host ← Device, Device, Vendor
bRequest	PS_OC_GET
wValue	0x0000
wIndex	0x0000
wLength	0x0001
Data	BIT0 = Analog, BIT1 = Digital

Note: BITx = 1, supply is over-current.
Note: BITx = 0, supply is NOT overcurrent

Acknowledge over-current¶

bmRequestType	Host → Device, Device, Vendor
bRequest	PS_OC_ACK
wValue	HIGH8(0) LOW8(value)
wIndex	0x0000
wLength	0x0000
Data	None

Note: BIT0 = Analog, BIT1 = Digital.
Note: BITx = 1 mean Acknowledge, and BITx = 0 ignore the power unit.
Note: if a BITx is set and the crossponding unit is not having any over-current, then the request is STALLED.