C6 fails to read with --no-stub at same place every time, and different place but fails reliably with stub. (ESPTOOL-1373)

[tyeth]

Operating System

win11

Esptool Version

5.3.1

Python Version

3.14

Chip Description

esp32c6

Device Description

adafruit feather

Hardware Configuration

No response

How is Esptool Run

win term (pwsh)

Full Esptool Command Line that Was Run

esptool -t --no-stub read-flash --flash-size 4MB 0x0 (4*1024*1024) file.bin

Esptool Output

TRACE +0.000   Write 6 bytes:        c000000900c0
Reading from 0x00090000 [===>                          ]  14.1% 589824/4194304 bytes...
  TRACE +0.027   Read 4096 bytes:
    c0efa06cd23245ef dbdcbcdeaa8509e5 | ...l.2E.........
    1305dbdc41efdbdc acc62285ef105fd0 | ....A....."..._.
    f240624439450561 828015cd411106c6 | .@bD9E.a....A...
    8947630af5008d47 630bf5008547631e | .Gc....Gc....Gc.
    f500eff02fba1305 dbdc41efdbdc6cc3 | ..../.....A...l.
    37451a4213054590 efa06cf537351a42 | 7E.B..E...l.75.B
    13058550efa0acf4 8280797137d71a42 | ...P......yq7..B
    1c082e8513074770 b2853686914606d6 | ......Gp..6..F..
    22d426d2efdbdc0c 92424593055054ef | ".&......BE..PT.
    f00fb203564101e2 460347c101b7d51a | ....VA..F.G.....
    422a849385457213 05dbdc0432c636c4 | B*...Er.....2.6.
    3ac2efdbdc3c9a12 47a2463246a285aa | :....<..G.F2F...
    84ef109fadeff0bf f6b2502254268592 | ..........P"T&..
    5445618280411106 c6efdbdc3ce2ef20 | TEa..A......<..
    011eb24006051365 1500410182800111 | ...@...e..A.....
    06ce22cc2ec6efdb dc7ce02a843245ef | .."......|.*.2E.
    dbdcfcdfaa852285 ef20213eaa852ac6 | ......".. !>..*.
    9710fcfde780408e 09edb245b7078080 | ......@....E....
    13f5c5ff13652500 3e95f24062440561 | .....e%.>..@bD.a
    8280370540000905 cdbf411106c622c4 | ..7.@.....A...".
    2a84efd0ac9fefdb dc7ccb19e537251a | *........|...7%.
    421305450aefa06c e9aa8505460145ef | B..E...l....F.E.
    202131ef106db1aa 8522852244b24011 |  !1..m..."."D.@.
    4641016fd04c9f01 1122cc06ce2ec6ef | FA.o.L..."......
    dbdcfcc72a843245 efdbdc7cc7635585 | ....*.2E...|.cU.
    000145efa02cde05 46b305c5002285ef | ..E..,..F...."..
    20412d6244f24005 616f102dad011122 |  A-bD.@.ao.-..."
    cc26ca4ec652c406 ce4ac82a848841ae | .&.N.R...J.*..A.
    89054aefdbdcdcc3 aa84631a44016340 | ..J.......c.D.c@
    a00837151a421305 851defa0ccd903a5 | ..7..B..........
    4900efdbdcfcc189 472a896312f40252 | I.......G*.c...R
    86e3d1a4feca8526 85ef20c1276244f2 | .......&.. .'bD.
    40d2444249b24922 4a05616f102da703 | @.DBI.I"J.ao.-..
    a58900efdbdcfcbe 2a86b3079940635d | ........*....@c]
    a000aa97fd17b3c7 c702e346f0fc3725 | ...........F..7%
    1a42130545ac5db7 01c5aa978507e5b7 | .B..E.].........
    37451a429305d057 1305c5eeefa0acdd | 7E.B...W........
    2a892286814445b7 411106c6efdbdc7c | *."..DE.A......|
    ba9307000263f5a7 000145efa0ecd013 | .....c....E.....
    75f50fef20e11db2 4041016f10cda441 | u... ...@A.o...A
    1106c6efdbdc1cba ef20c11ab2403945 | ......... ...@9E
    41018280011106ce ef202123aa852ac6 | A........ !#..*.
    9700fcfde780dbdc 7501edb245b70780 | ........u...E...
    80f19993e52500ae 97f2403e85056182 | .....%....@>..a.
    80b70740008907cd bf411106c6ef109f | ...@.....A......
    be19c1ef200018b2 4041018280011106 | .... ...@A......
    ce2ac6eff07ffe32 45ef101fc6f24005 | .*.....2E.....@.
    616f100d99011106 ce22cc2ec62a84ef | ao......."...*..
    f0bffc3245efdbdc 1cb0aa852285ef10 | ...2E......."...
    3fc4f24062443945 05618280011106ce | ?..@bD9E.a......
    2ac6eff09ffa3245 ef105fbef2400561 | *.....2E.._..@.a
    6f102d95011106ce 22cc2ec62a84eff0 | o.-....."...*...
    dff83245efdbdc3c acaa852285ef10bf | ..2E...<..."....
    bef2406244394505 618280411106c6ef | ..@bD9E.a..A....
    101fb6b240394541 018280797137e71a | ....@9EA...yq7..
    425c081307478b2e 85b28536868d4606 | B\...G.....6..F.
    d622d4efb03ce352 4593056054eff02f | ."...<.RE..`T../
    832a846245930570 54eff06f82b7e51a | .*.bE..pT..o....
    422ac69385c58c71 45efdbdcaceb3246 | B*.....qE.....2F
    a2852ac4ef107f9d 2245f245ef107fb9 | ..*....."E.E....
    b250225422454561 82800111480006ce | .P"T"EEa....H...
    ef109fb84800ef10 2077f24005618280 | ....H... w.@.a..
    01112e854c0006ce ef10d0004800ef10 | ....L.......H...
    5fb9f24039450561 8280411106c6ef10 | _..@9E.a..A.....
    9fbcb24041016f10 ed8741112e8506c6 | ...@A.o...A.....
    efdbdc9c9fef107f bbb2403945410182 | ..........@9EA..
    8041112e85b28501 4606c6efb07cbdb2 | .A......F....|..
    4037e51a42130545 a141018280b74782 | @7..B..E.A....G.
    4023a8a7da394582 80b7e71a42374782 | @#...9E.....B7G.
    40938747a12328f7 da8280b747824003 | @..G.#(.....G.@.
    a507dbdd01119305 dbdc3806ceefa02c | ..........8....,
    f44c00ef10407848 00ef10206df24005 | .L...@xH... m.@.
    618280411106c6ef 20813319c1ef10d0 | a..A.... .3.....
    7cb2404101828001 1106ce2ac6eff07f | |.@A.......*....
    fe3245ef200162f2 409355f54105616f | .2E. .b.@.U.A.ao
    003dff411106c6ef 20b107b240394541 | .=.A.... ...@9EA
    018280797106d622 d426d24ad0b2842a | ...yq..".&.J...*
    842ec6eff01ffb32 45efdbdc3c932a89 | .......2E...<.*.
    19464c082685efdb dc9cf25008ca8522 | .FL.&......P..."
    85ef20e16b635605 003305a040efb0cc | .. .kcV..3..@...
    acb2502254925402 5939454561828001 | ..P"T.T.Y9EEa...
    1106ce2ac6eff01f f73245ef20217e63 | ...*.....2E. !~c
    5605003305a040ef b02caaf240394505 | V..3..@..,..@9E.
    618280797106d622 d426d24ad0b2842a | a..yq..".&.J...*
    842ec6eff03ff432 45efdbdc5c8c2a89 | .....?.2E...\.*.
    15464c082685efdb dcbceb5008ca8522 | .FL.&......P..."
    85ef20d100635605 003305a040efb0ec | .. ..cV..3..@...
    a5b2502254925402 5939454561828079 | ..P"T.T.Y9EEa..y
    7137e71a425c0813 0707a52e85b28536 | q7..B\.........6
    868d4606d622d4ef b07cc252459305f0 | ..F.."...|.RE...
    62ef903fe2b7e51a 422a84938585a613 | b..?....B*......
    050002efdbdc8ccb f2466246a2852ac6 | .........FbF..*.
    ef20214fb2502254 324545618280098a | . !O.P"T2EEa....
    aa8711c638410545 1377070819cf4111 | ....8A.E.w....A.
    2e85314693858703 06c697107dfee780 | ..1F........}...
    4036b24001454101 82808280411106c6 | @6.@.EA.....A...
    ef20b120b2403945 41018280397137e7 | . . .@9EA...9q7.
    1a423c08130747b1 2e85b28536869946 | .B<...G.....6..F
    06deefb0dcb97245 93055034efe0dfd9 | ......rE..P4....
    2ac6624593050063 ef90dfd82ac4efb0 | *.bE...c....*...
    5053b7e71a429387 47b41cc10348c102 | PS...B..G....H..
    92570257a2563246 a2452ac2ef20b11f | .W.W.V2F.E*.. ..
    f250124521618280 411106c6ef200fb2 | .P.E!a..A.... ..
    b240060513651500 41018280011136c6 | .@...e..A.....6.
    06ceef20cfa6b246 635605003305a040 | ... ...FcV..3..@
    88c27d55f2400561 8280011136c606ce | ..}U.@.a....6...
    ef200f97b2466356 05003305a04088c2 | . ...FcV..3..@..
    7d55f24005618280 411122c406c6b947 | }U.@.a..A."....G
    2a84638af5022e85 efdbdcbc84b7d719 | *.c.............
    4283a5073b9700fc fde780002c9700fc | B...;.......,...
    fde7804025aa8522 85ef200faab24022 | ...@%..".. ...@"
    44394541018280fd 55fdb7797106d622 | D9EA....U..yq.."
    d426d24ad04ece9c 41c8412e84be84ef | .&.J.N..A.A.....
    dbdc2cf02a890844 efdbdcacefaa8948 | ..,.*..D.......H
    449377150099eb93 7735008deb1841b7 | D.w.....w5....A.
    f71942938707dd63 13f702efdbdc8cef | ..B....c........
    11472ac2b306e100 4e86ca852685ef20 | .G*.....N...&..
    6fa4635305023305 a040efb06c879307 | o.cS..3..@..l...
    25fce9df930725fe f1dbdd15464c00ef | %.....%.....FL..
    dbdc9cca92462247 c9bfb25022549254 | .....F"G...P"T.T
    0259f24939454561 8280411122c42a84 | .Y.I9EEa..A.".*.
    2e8506c6efdbdc1c 9efd5511e1814522 | ..........U...E"
    85ef20ef9eb24022 4439454101828039 | .. ...@"D9EA...9
    7122dc26da2a84b2 842e8515464c1006 | q".&.*......FL..
    deefdbdc9cc57008 89452685efdbdcfc | ......p..E&.....
    88f2470c108843ef 40cdbbf2472ac6c8 | ..G...C.@...G*..
    43efdbdc8ce3b245 6358050037151a42 | C......EcX..7..B
    1305c541ef90dcf9 a25712570256aa86 | ...A.....W.W.V..
    2285ef20cf94ef00 9dcdf2506254d254 | ".. .......PbT.T
    21618280011122cc 26ca06ce2a84ae84 | !a....".&...*...
    ef10dff101c52545 efa0fcfa2285ef10 | ......%E...."...
    5ff119e1efa09cf5 15464c002685efdb | _........FL.&...
    dcfcbd2246924522 85ef20cf8efd57e3 | ..."F.E".. ...W.
    03f5feef00ddc8f2 406244d244056182 | ........@bD.D.a.
    80011122cc26ca06 ceaa842e84ef101f | ...".&..........
    ed01c52545efa03c f62685ef109fec19 | ...%E..<.&......
    e1efa0dcf0228515 464c00efdbdc3cb9 | ....."..FL....<.
    7d54224619e63945 f2406244d2440561 | }T"F..9E.@bD.D.a
    828092452685ef20 0f89e30c85fca247 | ...E&.. .......G
    1247898f2a973ec4 3ac2e1dfeff0add4 | .G..*.>.:.......
    efa0117979d50145 c1bf797122d426d2 | ...yy..E..yq".&.
    4ad006d69c412a89 2e843e85be84ef10 | J....A*...>.....
    1fe601c52545efa0 3cef484019464c08 | ....%E..<.H@.FL.
    efdbdcfcb28d4762 466300f902054519 | ......GbFc....E.
    c6d2452685ef10df fdef009dbdb25022 | ..E&..........P"
    5492540259456182 80084432c6efdbdc | T.T.YEa...D2....
    0cd032466358a600 37251a4213054556 | ..2FcX..7%.B..EV
    ef905ce6e355a0fc e353c5fc2a86d1b7 | ..\..U...S..*...
    797122d419462a84 2e854c0806d6efdb | yq"..F*...L.....
    dc3cad6246d24514 082285ef107fe0ef | .<.bF.E.."......
    005db82ac66c0009 45ef501db5b25022 | .].*.l..E.P...P"
    5445618280411122 c42a842e8506c6ef | TEa..A.".*......
    dbdc0ccaaa852285 ef107fdcb2402244 | ......"......@"D
    3945410182807971 300822d42a842e85 | 9EA...yq0.".*...
    894506d6efdbdcec ebe2476c088843ef | .E........Gl..C.
    40cd9ee2472ac6c8 43efdbdc8cc6b245 | @...G*..C......E
    6358050037151a42 1305c541ef90dcdc | cX..7..B...A....
    7246aa862285ef10 ffc7b25022543945 | rF.."......P"T9E
    4561828079713008 22d42a842e858945 | Ea..yq0.".*....E
    06d6efdbdc2ce7e2 476c088843ef400d | .....,..Gl..C.@.
    9ae2472ac6c843ef dbdcccc1b2456358 | ..G*..C......EcX
    050037151a421305 c541ef901cd87246 | ..7..B...A....rF
    aa862285ef109fa3 19c1efa07cdbddb2 | ..".........|...
    5022543945456182 8001116c0006ceef | P"T9EEa....l....
    107f9a2ac42c0009 45ef507da7f24005 | ...*.,..E.P}..@.
    618280411106c6ef 10dfbfb240394541 | a..A........@9EA
    0182808841411106 c6ef10bfbeb24039 | ....AA........@9
    4541018280011106 ce22cc26ca0d4763 | EA.......".&..Gc
    98e50213741600aa 8411c432c6ef103f | ....t......2...?
    f332462a84118a11 c62685ef109ff60a | .2F*.....&......
    05498cf240228562 44d24405618280d9 | .I..@".bD.D.a...
    479cc27d54fdb701 1106ce22cc9c4137 | G..}T......"..A7
    e71a421307c7d33e 848d465c0091057d | ..B....>..F\...}
    15efb00cdbddb246 224692452285ef10 | .......F"F.E"...
    cff5f24062440561 8280797106d622d4 | ...@bD.a..yq..".
    9c4137e71a421307 c7d03e8499463c00 | .A7..B....>..F<.
    91057d15efb0ecd7 2245ef307df97248 | ..}....."E.0}.rH
    e2475247c2463246 aa852285ef10bffc | .GRG.F2F..".....
    b250225445618280 2e85b28537060200 | .P"TEa......7...
    0111090606ce22cc 36c6efb04cceb246 | ......".6...L..F
    b7e51a42938545d5 9c4211453e84efb0 | ...B..E..B.E>...
    5cf3a2852ac6ef10 5ff3f24062443245 | \...*..._..@bD2E
    0561828079710a86 93050004080806d6 | .a..yq..........
    ef00dc8237361a42 b75519421306862c | ....76.B.U.B...,
    9385051a0a85ef10 8cb9f55708083ec4 | ...........W..>.
    ef209dfe2ac637e5 1a42300089451305 | . ..*.7..B0..E..
    05e3eff06c8feff0 cbd2411122c42a84 | ....l.....A.".*.
    2e8506c6efdbdc0c ddaa852285ef20c1 | ...........".. .
    58b2402244394541 018280411106c6ef | X.@"D9EA...A....
    204157b240133515 003305a040019913 |  AW.@.5..3..@...
    05e5034101828088 41411106c6ef20c1 | ...A....AA.... .
    53b2403945410182 80011126ca06ce22 | S.@9EA.....&..."
    cc9c4137e71a4213 07c7ea9105be848d | ..A7..B.........
    465c007d15efb0ec c692473947930520 | F\.}......G9G..
    336397e700224463 0af4009305703337 | 3c..."Dc.....p37
    451a421305850eef a07cb03245ef305d | E.B......|.2E.0]
    e6aa852685ef2021 4bf24022856244d2 | ...&.. !K.@".bD.
    4405618280011122 cc15662e84aa8537 | D.a...."..f....7
    451a421306667f13 05455906ceef90fc | E.B..f...EY.....
    d030009305d007ef 905cef3000814501 | .0.......\.0..E.
    45ef903cd1a28515 46efdbdc0cfaf240 | E..<....F......@
    6244056182807971 06d622d49c4137e7 | bD.a..yq.."..A7.
    1a421307c7e98946 91057d153e848a87 | .B.....F..}.>...
    efb04cbd02452c00 eff0fff91245b947 | ..L..E,......E.G
    630ff5004c08eff0 1ff9228550082c00 | c...L.....".P.,.
    ef200148b2502254 3945456182803146 | . .H.P"T9EEa..1F
    2c00480897107dfe e78020c8f9bf0111 | ,.H...}... .....
    22cc06ce9c4137e7 1a428d467d153e84 | "....A7..B.F}.>.
    130747e85c009105 efb0ccb73245b947 | ..G.\.......2E.G
    81466305f500ef30 ddd8aa8603468100 | .Fc....0.....F..
    81ca19c637351a42 130545deef903ca7 | ....75.B..E...<.
    92452285ef202166 f240624405618280 | .E".. !f.@bD.a..
    01112e85b2850946 06ceefb06cadb7e5 | .......F....l...
    1a42938545ec1305 dbdc02efb03cd12a | .B..E........<.*
    c6ef20e137f24032 450561828049712a | .. .7.@2E.a..Iq*
    c60810232611162e c832ca36cc3aceef | ...#&....2.6.:..
    f0abaded5728103e c29700fcfde78040 | ....W(.>.......@
    821de56246d24532 45c24782972ac2ef | ...bF.E2E.G..*..
    f02bad924763d807 007247b307f0401c | .+..Gc...rG...@.
    c3fd573ec28320c1 1612457561828092 | ..W>.. ...Eua...
    5708103ec4eff04b a9281097f0fbfde7 | W..>...K.(......
    80207e61f9224593 05603eef903cdfef | . ~a."E..`>..<..
    dbdcac84b307a040 3ec25dbf3687b286 | .......@>.].6...
    2e86b73505429385 05656ff05ff73687 | ...5.B...eo._.6.
    b2862e86b7350542 938505616ff03ff6 | .....5.B...ao.?.
    411106c6ef20311e b240394541018280 | A.... 1..@9EA...
    411106c6ae87d445 90458843cc41ef20 | A......E.E.C.A.
    911ab24039454101 8280411122c42a84 | ...@9EA...A.".*.
    2e8506c6efdbdc4c b4b94511e1854522 | .......L..E...E"
    85ef20711ab24022 4439454101828001 | .. q..@"D9EA....
    1122cc26ca06ce2a 84ae84ef20510e01 | .".&...*.... Q..
    c52545efa05c9722 85ef20110e19e1ef | .%E..\.".. .....
    a0fc9115464c0026 85efdbdc4cda2246 | ....FL.&....L."F
    92452285ef20817f fd57e303f5feef00 | .E".. ...W......
    2de5f2406244d244 05618280797122d4 | -..@bD.D.a..yq".
    26d24ad006d69c41 2a892e843e85be84 | &.J....A*...>...
    ef20110901c52545 efa01c9248401946 | . ....%E....H@.F
    4c08efdbdcccd58d 4762466300f90205 | L.......GbFc....
    4519c6d2452685ef 206176ef006de0b2 | E...E&.. av..m..
    5022549254025945 618280084432c6ef | P"T.T.YEa...D2..
    b0fcf232466358a6 0037251a42130545 | ...2FcX..7%.B..E
    56ef903c89e355a0 fce353c5fc2a86d1 | V..<..U...S..*..
    b7411122c42a842e 8506c6efb03cf0aa | .A.".*.......<..
    852285ef207103b2 4022443945410182 | .".. q..@"D9EA..
    80411106c6ef2041 7eb2403945410182 | .A.... A~.@9EA..
    80011122cc2e8426 ca7000aa84894522 | ..."...&.p....E"
    8506ceefdbdccc90 2685a285ef206175 | ........&.... au
    f2406244d2443945 056182806f209100 | .@bD.D9E.a..o ..
    411106c6ef202175 b240394541018280 | A.... !u.@9EA...
    8841411106c6ef20 0174b24039454101 | .AA.... .t.@9EA.
    8280011106ce22cc 26ca0d476398e502 | ......".&..Gc...
    13741600aa8411c4 32c6ef2051053246 | .t......2.. Q.2F
    2a84118a11c62685 ef2091080a05498c | *.....&.. ....I.
    f24022856244d244 05618280d9479cc2 | .@".bD.D.a...G..
    7d54fdb7b7e51a42 0111938545ec1305 | }T.....B....E...
    dbdc0206ceefb0fc a72ac6ef20d108f2 | .........*.. ...
  TRACE +2.998   Packet content transfer stopped

Hard resetting via RTS pin...

A fatal error occurred: Packet content transfer stopped

More Information

See https://github.com/tyeth/esptool/pulls

• fix(loader): Escape trace hex dump as a whole to avoid Rich MarkupError tyeth/esptool#4
• fix(esp32): Recover ROM read_flash_slow from stalled responses tyeth/esptool#5

and related https://github.com/tyeth/esptool/issues
tyeth#1
tyeth#2
tyeth#3

There's a patch for a pattern recognition bug (the with stub error) [PR 4].
For the --no-stub version here's a hacky fix and retry logic in the second PR that's worth discussion as presumably the main rom can't be fixed [PR 5].

Other Steps to Reproduce

No response

I Have Read the Troubleshooting Guide

• I confirm I have read the troubleshooting guide.

[github-actions]

Hi @tyeth! Please be aware that (1) the following suggestions are generated by a bot and haven't been fact-checked by Espressif Systems, (2) burning eFuses and enabling security features are irreversible operations and can damage your ESP32 device. We hope that this message will help you until an Espressif Engineer looks at your issue.

---

I'm sorry, but the knowledge sources provided do not contain any information relevant to this esptool issue regarding the ESP32-C6 failing to read flash with --no-stub or with the stub loader.

The knowledge sources only contain raw image asset data (pixel byte arrays) from Espressif's esp-dev-kits and esp-bsp repositories, which are completely unrelated to this esptool flash reading problem.

To get help with this issue, I'd recommend:

1. Checking the official esptool troubleshooting guide at https://docs.espressif.com/projects/esptool/en/latest/esp32/troubleshooting.html

2. Reviewing the esptool GitHub issue tracker directly at https://github.com/espressif/esptool/issues for similar reports.

3. Looking at the patches referenced in the issue — the reporter has already submitted PRs (PR #4 and PR #5) that may address the root cause, and those would be worth reviewing and potentially upstreaming to the main esptool repository.

4. Trying a different USB cable or host port, as Packet content transfer stopped errors can sometimes be caused by USB connectivity issues, especially on Windows.

I'd suggest directing the customer to engage directly on the esptool GitHub issue where Espressif engineers can review the proposed patches.

[tyeth]

trace from normal esptool (5.3.1):
output.txt

flash that exhibits the read-flash issue (needs flashing to C6 4MB at 0x0):
file.zip

[tyeth]

@radimkarnis this might be the thing that caused #1136.
If you cannot recreate, then at least the code theory of tyeth#4 should make sense (two separate concurrent pattern matching situations but with different terminator rules)
If you're happy I'll PR that to upstream.

If there's anything to be gained by discussion of my PR number 5 then great, otherwise I'll just keep it kicking around for those stub free moments.

[tyeth]

no stub:

PS C:\dev\python\cpython\esptool> esptool --no-stub read-flash --flash-size 4MB 0x0 (4*1024*1024) file.bin
esptool v5.3.1
Connected to ESP32-C6 on COM4:
Chip type:          ESP32-C6FH4 (QFN32) (revision v0.1)
Features:           Wi-Fi 6, BT 5 (LE), IEEE802.15.4, Single Core + LP Core, 160MHz, Embedded Flash 4MB
Crystal frequency:  40MHz
USB mode:           USB-Serial/JTAG
MAC:                40:4c:ca:ff:fe:59:7b:e4
BASE MAC:           40:4c:ca:59:7b:e4
MAC_EXT:            ff:fe


Enabling default SPI flash mode...
Configuring flash size...
Reading from 0x00002400 [                              ]   0.2% 9216/4194304 bytes... Note: Consider specifying the flash size argument.

Hard resetting via RTS pin...

A fatal error occurred: Packet content transfer stopped
PS C:\dev\python\cpython\esptool> esptool --no-stub read-flash --flash-size 4MB 0x0 (4*1024*1024) file.bin
esptool v5.3.1
Connected to ESP32-C6 on COM4:
Chip type:          ESP32-C6FH4 (QFN32) (revision v0.1)
Features:           Wi-Fi 6, BT 5 (LE), IEEE802.15.4, Single Core + LP Core, 160MHz, Embedded Flash 4MB
Crystal frequency:  40MHz
USB mode:           USB-Serial/JTAG
MAC:                40:4c:ca:ff:fe:59:7b:e4
BASE MAC:           40:4c:ca:59:7b:e4
MAC_EXT:            ff:fe


Enabling default SPI flash mode...
Configuring flash size...
Reading from 0x00002400 [                              ]   0.2% 9216/4194304 bytes... Note: Consider specifying the flash size argument.

Hard resetting via RTS pin...

Stub:

esptool read-flash --flash-size 4MB 0x0 (4*1024*1024) file.bin
esptool v5.3.1
Connected to ESP32-C6 on COM4:
Chip type:          ESP32-C6FH4 (QFN32) (revision v0.1)
Features:           Wi-Fi 6, BT 5 (LE), IEEE802.15.4, Single Core + LP Core, 160MHz, Embedded Flash 4MB
Crystal frequency:  40MHz
USB mode:           USB-Serial/JTAG
MAC:                40:4c:ca:ff:fe:59:7b:e4
BASE MAC:           40:4c:ca:59:7b:e4
MAC_EXT:            ff:fe

Stub flasher running.

Configuring flash size...
Reading from 0x00090000 [===>                          ]  14.1% 589824/4194304 bytes...
Hard resetting via RTS pin...

A fatal error occurred: Packet content transfer stopped
PS C:\dev\python\cpython\esptool> esptool read-flash --flash-size 4MB 0x0 (4*1024*1024) file.bin
esptool v5.3.1
Connected to ESP32-C6 on COM4:
Chip type:          ESP32-C6FH4 (QFN32) (revision v0.1)
Features:           Wi-Fi 6, BT 5 (LE), IEEE802.15.4, Single Core + LP Core, 160MHz, Embedded Flash 4MB
Crystal frequency:  40MHz
USB mode:           USB-Serial/JTAG
MAC:                40:4c:ca:ff:fe:59:7b:e4
BASE MAC:           40:4c:ca:59:7b:e4
MAC_EXT:            ff:fe

Stub flasher running.

Configuring flash size...
Reading from 0x00090000 [===>                          ]  14.1% 589824/4194304 bytes...
Hard resetting via RTS pin...

A fatal error occurred: Packet content transfer stopped

Same at other baud rates.

[dobairoland]

Hi @tyeth. I've reproduced this issue and submitted the fix at espressif/esp-flasher-stub#106.

[dobairoland]

I'm closing this because the issue has been fixed in the master branch and will be available in the next release. The linked esp-flasher-stub PR is just an optional improvement and is not needed to solve this.

[tyeth]

Hey @dobairoland thanks for the fix. What's the situation with the --no-stub issue?

[dobairoland]

--no-stub part of the issue: I have submitted a ROM issue report as well as proposed a workaround for esptool. These are now under review.

[tyeth]

Hi Roland, you are a super star, thank you so much!

…

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