This page describes how to make a clone of a Dell PA-10 AC adapter. More specifically, an HP adapter is taken which has the same jack. From this the voltage is modified to 19.5 volt. For the laptop, to recognize the correct power it can source, a PIC 10f220 controller is taken to generate a data signal to the laptop.

Although I have lying around a ST7-Lite pic controller with ST7-STICK interface, I don't have a windows machine with a parallel port. So I decided to use a pic controller instead which can be programmed under linux with PICPgm.

• http://www.computerbanter.com/showpost.php?p=928842&postcount=21
• http://picpgm.picprojects.net/download.html PICPgm is used to program the PIC controller
• http://sourceforge.net/projects/hex2bin/?source=dlp To decompile intel hex file on a mac

The ST7-STICK interface can be used with PICPgm, using the following pgmifcfg.xml configuration file which needs to be in the users home directory:

ToDo

The intel pic hex format is described here, here and here.

• A word is 12 bits in size. the remaining 4 bits are not used for data. I don't understand how 2805 is encoded into memory. This is an indication the code is for another processor.
• The 'Extended Linear Address Record' in the first line does not make much sense for the PIC 10f220. See here for more information.
• The device ID is stored from 0x2000 to 0x2003 As is explained here.
• The processor configuration is stored at 0x2007. For a 10f220 this would be: IOSCFS=8MHz, _MCPU=Pull-up enabled, WDTE=disabled, _CP=disabled, MCLRE=MCLR function

:020000040000FA                             ; Byte count=2, Address=0000, RECTYP=04, DATA=0000 ; 1 word of 2-byte data with RECTYP='Extended Linear Address Record', starting at 0000, checksum=FA. Bits 16-31 of the LBA are set to 0, bits 0-15 of the LBA are taken from the subsequent records. Since there is no further extended linea address, this remains effective throughout the code.
 
:0800080005281F28A300A40035                 ; Byte count=8, Address=0008, RECTYP=00, DATA=05281F28A300A400 ; 4 words, starting at word (8/2)=4, data in low-high format:2805,281f,00a3,00a4
:100010000830A2002508A306A30C2508A300031C92 ; Byte count=16, Address=0010, RECTYP=00, DATA=0830A2002508A306A30C2508A300031C; 8 words, starting at word (0x10/2)=8, data in low-high format:3008,00a2,0825,06a3,0ca3,0825,00a3,3100
:1000200013281830A306A30C2308A5002408A30056 ; etc
:100030000310A30C2308A400A20B0A280800A501A2
:10004000F0300620103006200000003006200000AE
 
:084000000100020003000400AE                 ; Byte count=8, Address=4000, RECTYP=00, DATA=0100020003000400, 4 words, starting at word (0x4000/2)=0x2000, data in low-high format:0001,0002,0003,0004
:02400E00F93F78 ; Byte count=2, Address=400E, RECTYP=00, DATA=F93F, 1 word, starting at word (0x400E/2)=0x2007, data in low-high format:3ff9
:00000001FF                                 ; EOF

With gputils (v1.2.0) this is converted with the following command:

./gpdasm -p p10f220 -i dell.hex

A memory dump could be created with this command:

./gpdasm -p p10f220 -m dell.hex

But the output does not reflect the hex values in the second column from the code above. Therefore the list below is generated with another method.

00000000  0000 0000 0000 0000 2805 281f 00a3 00a4 ......(.(.(.....
00000008  3008 00a2 0825 06a3 0ca3 0825 00a3 1c03 ...%.......%....
00000010  2813 3018 06a3 0ca3 0823 00a5 0824 00a3 0......#.#...$..
00000018  1003 0ca3 0823 00a4 0ba2 280a 0008 01a5 ...#......(.....
00000020  30f0 2006 3010 2006 0000 3000 2006 0000 .0. .....0. ...
00002000  0001 0002 0003 0004                     ........
00002007  3ff9                                    ?.

As this disassembly code in the first column does not make much sense, I assumed another microcontroller had been used but had been mistaken with the 10f220. With this very practical alternative freeware disassembler, which gives a slightly better output than gpdasm, while changing the PIC-Type, it will immediately show the updated disassembly. This makes it much easier to find the target for which the code was written. So far following controllers show up with useful code:

• 12C: 12C671, 12C672
• 12F: 12F629
• 16C: 16C61, 16C62, 16C62A, 16C62B, 16C63, 16C63A, 16C64, 16C64A, 16C65, 16C65A, 16C65B, 16C66, 16C67, 16C71, 16C72, 16C72A, 16C73, 16C73A, 16C73B, 16C74, 16C74A, 16C74B, 16C76, 16C77, 16CR83, 16C84, 16CR84, 16C432, 16C433, 16C554, 16C558, 16C620, 16C620A, 16C621, 16C621A, 16C622, 16C622A, 16CE623, 16CE624, 16CE625, 16C641, 16C642, 16C661, 16C662, 16C710, 16C711, 16C712, 16C715, 16C716, 16C717, 16C745, 16C765, 16C770, 16C771, 16C773, 16C774, 16C781, 16C782, 16C923, 16C924, 16C925, 16C926
• 16F: 16F72, 16F73, 16F74, 16F76, 16F77, 16F83, 16F84, 16F84A, 16F616, 16F627, 16F627A, 16F628, 16F628A, 16F630, 16F636, 16F639, 16F648A, 16F676, 16F677, 16F684, 16F685, 16F687, 16F689, 16F690, 16F716, 16F785, 16F818, 16F819, 16F870, 16F871, 16F872, 16F873, 16F873A, 16F874, 16F874A, 16F876, 16F876A, 16F877, 16F877A, 16F913, 16F914, 16F916, 16F917, 16F946
• Other: 14000, 16HV616, 16HV785

No meaningful disassembly from the following types:

• 10F: 10F200, 10F202, 10F204, 10F206, 10F220, 10F222
• 12F: 12F508, 12F509, 12F510, 12F519, 12F609, 12F615, 12F635, 12F675, 12F683
• 12C: 12C508, 12C508A, 12C509, 12C509A, 12CE518, 12CE519, 12CE673, 12CE674
• 16C: 16C52, 16C54, 16C54A, 16C54B, 16C54C, 16C55, 16C55A, 16C56, 16C56A, 16C57, 16C57A, 16C58A, 16C58B, 16C505
• 16F: 16F54, 16F57, 16F59, 16F87, 16F88, 16F505, 16F506, 16F526, 16F610, 16F631, 16F688, 16F722, 16F723, 16F724, 16F726, 16F727, 16F737, 16F747, 16F767, 16F777, 16F882, 16F883, 16F884, 16F886, 16F887
• Other: 12HV609, 12HV615, 16HV540, 16HV610

Test the communications with the controller with:

avrdude -P usb -c dragon_isp -p attiny13 -v

With the attiny13 solution, program the microcontroller with:

avrdude -P usb -c dragon_isp -p attiny13 -Uflash:w:/Users/iudex/Downloads/tiny13-90w/Dell_1wire.hex:i
avrdude -P usb -c dragon_isp -p attiny13 -Ueeprom:w:/Users/iudex/Downloads/tiny13-90w/Dell_1wire.eep:i

The terminal mode can be entered with:

avrdude -P usb -c dragon_isp -p attiny13 -t

• see at this page for info about setting the fuses: http://www.engbedded.com/fusecalc

Connect Bus Pirate with 1-wire device as follows:

• (Bus Pirate) MOSI → (ATtiny13A) 1-wire data pin (to 47 ohm resistor)
• (Bus Pirate) GND → (ATtiny13A) GND

Because the ATtiny13A is not a genuine 1-wire ic, connect additionally:

• (Bus Pirate) +5v → (ATtiny13A) +5v

With Bus Pirate v4 an external pull-up resistor is not required. The board con be configured by software to have one. Connect the Bus Pirate and enter the following commands:

HiZ>m
1. HiZ
2. 1-WIRE
3. UART
4. I2C
5. SPI
6. 2WIRE
7. 3WIRE
8. KEYB
9. LCD
10. PIC
11. DIO
x. exit(without change)

(1)>2
Ready
1-WIRE>v
Pinstates:
#12    .#11    .#10    .#09   .#08   .#07   .#06   .#05   .#04   .#03   .#02   .#01   
GND.5.0V.3.3V.VPU.ADC.AUX2.AUX1.AUX.-.-.-.OWD
P.P.P.I.I.I.I.I.I.I.I.I.
GND.0.00V.0.00V.0.00V.0.00V.L.L.L.L.L.L.L.
1-WIRE>W
POWER SUPPLIES ON
1-WIRE>P
Pull-up resistors ON
Warning: no voltage on Vpullup pin
1-WIRE>e
Select Vpu (Pullup) Source:
 1) External (or None)
 2) Onboard 3.3v
 3) Onboard 5.0v

(1)>3
5V on-board pullup voltage enabled
1-WIRE>v
Pinstates:
#12    .#11    .#10    .#09   .#08   .#07   .#06   .#05   .#04   .#03   .#02   .#01   
GND.5.0V.3.3V.VPU.ADC.AUX2.AUX1.AUX.-.-.-.OWD
P.P.P.I.I.I.I.I.I.I.I.I.
GND.4.96V.3.34V.4.86V.0.00V.L.L.L.H.H.H.H.
1-WIRE>(0)
 0.Macro menu
Macro     1WIRE address
No device, try (ALARM) SEARCH macro first
1WIRE ROM COMMAND MACROs:
 51.READ ROM (0x33) *for single device bus
 85.MATCH ROM (0x55) *followed by 64bit address
 204.SKIP ROM (0xCC) *followed by command
 236.ALARM SEARCH (0xEC)
 240.SEARCH ROM (0xF0)

1-WIRE>(240)
SEARCH (0xF0)
Macro     1WIRE address
Device IDs are available by MACRO, see (0).

...
...
...

If you are ready, either type:

1-WIRE>e
Select Vpu (Pullup) Source:
 1) External (or None)
 2) Onboard 3.3v
 3) Onboard 5.0v

1-WIRE>p
Pull-up resistors OFF

(1)>1
 on-board pullup voltage disabled

1-WIRE>w
POWER SUPPLIES OFF

or type 'm', which will turn off all outputs, power supplies and pull-up resistors. It's ready to accept a new mode. Press 1 to return to HiZ mode:

1-WIRE>m
1. HiZ
2. 1-WIRE
3. UART
4. I2C
5. SPI
6. 2WIRE
7. 3WIRE
8. KEYB
9. LCD
10. PIC
11. DIO
x. exit(without change)

(1)>1
Ready
HiZ>

Searching with google for 1 wire emulator revealed following pages:

• https://xn--wp-gka.de/index.php?Dell-1wire Implementation in a ATtiny13 microcontroller for a 90W Dell power adapter
• http://www.mikrocontroller.net/attachment/128803/DELL_1wire_Emulator_Tiny85V.bas Implementation of a Dell 90w adapter replacement DS2501 with a ATTiny 85 V
• http://radiokot.ru/forum/viewtopic.php?f=2&t=33322 Implementation of a DS2432 in a PIC12F629 (Scroll down to the posting at the 28th of August 2010)
• http://avr.ru/ready/inter/1wire/1wire Emulation of the 1 wire protocol in a AtMega 16
• http://www.cczwei-forum.de/cc2/thread.php?postid=2359 ATM18:: 1-Wire Emulator project for a DS1820 Temperature sensor

Some information and a small video on defective parts on eevblog can be found here.

• http://www.laptop-junction.com/toast/content/inside-dell-ac-power-adapter-mystery-revealed
• http://www.howtofixcomputers.com/forums/dell/dell-pa-10-ac-adapter-center-pin-108608.html
• http://www.chzsoft.de/storage/2501unw.pdf datasheet Dallas Semiconductor DS2501 with 512 bits
• http://ww1.microchip.com/downloads/en/DeviceDoc/41270E.pdf Datasheet PIC10F220 from Microchip
• http://dangerousprototypes.com/docs/3EEPROM_explorer_board 1-wire tutorial with eeprom DS2431