Digispark - Bootloader stuck

Question

I have a digispark that I want to reprogram, soldered into a circuit. I have burned the default t85 micronucleus firmware.

This is the command I used:

"C:\Program Files (x86)\Arduino\hardware\tools\avr/bin/avrdude" -C "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf" -v -pattiny85 -cstk500v1 -PCOM4 -b19200 -Uflash:w:D:\Documents\micronucleus-master\firmware\releases\t85_default.hex:i
avrdude: Version 6.3, compiled on Sep 12 2016 at 17:24:16
 Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
 Copyright (c) 2007-2014 Joerg Wunsch
 System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"
 Using Port : COM4
 Using Programmer : stk500v1
 Overriding Baud Rate : 19200
 AVR Part : ATtiny85
 Chip Erase delay : 400000 us
 PAGEL : P00
 BS2 : P00
 RESET disposition : possible i/o
 RETRY pulse : SCK
 serial program mode : yes
 parallel program mode : yes
 Timeout : 200
 StabDelay : 100
 CmdexeDelay : 25
 SyncLoops : 32
 ByteDelay : 0
 PollIndex : 3
 PollValue : 0x53
 Memory Detail :
 Block Poll Page Polled
 Memory Type Mode Delay Size Indx Paged Size Size #Pages MinW MaxW ReadBack
 ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
 eeprom 65 12 4 0 no 512 4 0 4000 4500 0xff 0xff
 flash 65 6 32 0 yes 8192 64 128 30000 30000 0xff 0xff
 signature 0 0 0 0 no 3 0 0 0 0 0x00 0x00
 lock 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
 lfuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
 hfuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
 efuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
 calibration 0 0 0 0 no 1 0 0 0 0 0x00 0x00
 Programmer Type : STK500
 Description : Atmel STK500 Version 1.x firmware
 Hardware Version: 2
 Firmware Version: 1.18
 Topcard : Unknown
 Vtarget : 0.0 V
 Varef : 0.0 V
 Oscillator : Off
 SCK period : 0.1 us
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.03s
avrdude: Device signature = 0x1e930b (probably t85)
avrdude: safemode: hfuse reads as D7
avrdude: safemode: efuse reads as FF
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
 To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: reading input file "D:\Documents\micronucleus-master\firmware\releases\t85_default.hex"
avrdude: writing flash (8116 bytes):
Writing | ################################################## | 100% 0.07s
avrdude: 8116 bytes of flash written
avrdude: verifying flash memory against D:\Documents\micronucleus-master\firmware\releases\t85_default.hex:
avrdude: load data flash data from input file D:\Documents\micronucleus-master\firmware\releases\t85_default.hex:
avrdude: input file D:\Documents\micronucleus-master\firmware\releases\t85_default.hex contains 8116 bytes
avrdude: reading on-chip flash data:
Reading | ################################################## | 100% 0.07s
avrdude: verifying ...
avrdude: 8116 bytes of flash verified
avrdude: safemode: hfuse reads as D7
avrdude: safemode: efuse reads as FF
avrdude: safemode: Fuses OK (E:FF, H:D7, L:F1)
avrdude done. Thank you.

I have not set any fuses (I hope the frequency is right.)

The board is recognized by my computer and I can program a sketch into it using Arduino IDE. Despite all this the program I burned into it does not run. It seems it is stuck into the bootloader section.

The sketch:

void setup() {
 // initialize digital pin LED_BUILTIN as an output.
 pinMode(0, OUTPUT);
}
// the loop function runs over and over again forever
void loop() {
 digitalWrite(0, HIGH); 
}

Pin PB0 has never a voltage bigger than 1.7V(noise or floating). All pins have similar voltages (except PB3,PB4 which are pulled up or high)

The schematic: enter image description here

The circuit works. I tested both displays previously with the atiny which I directly programmed with the Uno. The upper right connector is directly plugged into the digispark with the following pins: VIN,GND,5V. The middle connector is also plugged into the digispark.

I have tried:

• Powered by USB: I am afraid this will be detected by the bootloader and enter the programming state thus never running the schematic(shouldn't happen but you never know...)
• Powered by VIN with a 9V battery. Nothing. All voltages are in check (5V pin has 5v on it. All other pins are floating)
• Powered by 5V pin using an Arduino UNO as the source. Nothing. In all cases the voltage on PB0 stays the same. It varies between 0.6V and 1.6V.

In Arduino IDE:

• Tried Digispark 16.5Mhz
• Digispark Pro 16Mhz
• Digispark(No Usb) 16Mhz

Always a succesfull uploading.

Notes:

• After uploading in Arduino this text comes up:

  Starting the user app ... running: 100% complete

  So it is supposed to run the program but the board actually resets because it gets renumerated by windows.

• It's not quite possible to de-solder it and program the sketch directly with Arduino as ISP

• I use Windows 10
• Fuses used when I burned the micronucleus L:F1 H:D7 E:FF. These are the default "safe" values. The actual fuses needed by the firmware are L:E1 H:DD E:FE.
• Difference in extended fuse: Self-programming is curently disabled...Is this the culprit?
• I managed to desolder PB0,PB1 and PB2 from the back of the pcb. Now I can't program it directly with Arduino as ISP. The setup I have should work because I can easily program an t45. So it has something to do with the digispark. Checked the connection between pins and the actual MCU. The error I get is Yikes... and sometimes it finds an 0x00ff00 or other junk id for the board but probably it's because of misconnection.

Question #2:

In the current configuration(soldered) would it be possible to use again Arduino as ISP to program it? PB0,PB1,PB2 are connected to Serial Clock,Serial Data and Serial Storage Clock respectively. I am trying right now to set the right fuses but every time I get this:

avrdude -C "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf" -c stk500v1 -p attiny85 -U lfuse:w:0xe1:m -U hfuse:w:0xdd:m -U efuse:w:0xfe:m -B 20 -b19200 -P COM7
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.06s
avrdude: Device signature = 0x000000 (retrying)
Reading | ################################################## | 100% 0.05s
avrdude: Device signature = 0x000000 (retrying)
Reading | ################################################## | 100% 0.05s
avrdude: Device signature = 0x000000
avrdude: Yikes! Invalid device signature.
 Double check connections and try again, or use -F to override
 this check.
avrdude done. Thank you.
make: *** [fuse] Error 1

• Ron Beyer: Your schematic needs some work. For example the connector(?) in the upper right corner, I can't tell what order the pins are in. I can't tell what the names of the resistors are (because they layer on top of each other). There are dangling wires (stubs) and it seems like a lot of spaghetti. There are no capacitors anywhere so that might be an issue.
• sergiu reznicencu: The upper connector is for power. It is directly pulled into digispark. So is the middle connector. Digispark already provide the capacitors for the power. And yes..It still needs a lot of work. BUT the schematic works. Tested both screens with numbers by directly programming the attiny.
• sergiu reznicencu: This is driving me crazy. Since I programmed this bootloader nothing works. I think it is software related because the board works..in its way. It is recognized by the pc, I can program it..but it executes nothing it should have.
• jsotola: have you read this? digistump.com/wiki/digispark/tutorials/connecting
• sergiu reznicencu: I programmed the digisprk a hundred times before. It always worked.

Answer 1

Solved it! I don't know what the real issue was but I constructed a HV programmer and just blasted the digispark with the new and proper fuses. Now it works as it should.