E320 · Source-scoped pinout variants

5-pin DIN connector: MIDI and legacy uses engineering reference

Named wiring from the pinout research; connector shape alone does not establish capabilities.

Open field note Source trail

Source checked · no independent review claimed · Fabrication approved: no

5-pin DIN (180-degree; MIDI and legacy uses) engineering reference original orientation schematic — Original pinout diagram; read the exact variant and view below. Not to scale.

Contact count

Not asserted

Source-scoped connector interface

Mating boundary

Shape is not the verdict.

Check the exact device and mating connector.

Orientation

How to read this profile

Read the exact variant view convention. Schematic layouts do not establish physical positions.

Source-scoped identification facts

Each value retains its exact example, role and measurement axis. Facts from different parts must not be combined into an invented component.

Documented examples; not a mating drawing or compatibility approval
Nominal contacts	5S089Nominal contact count; some implementations may omit populated positions. It is not a wiring map.
Connector role	plug (NYS322)S617Named source examples retain separate role, part, view and axis limits; values are not a universal family specification. NYS322. Documented role: plug. 6.5mmmaximum cableOD is wire acceptance,not shell diameter.; NYS322drawingS618full text provides59.5,13.35diameter,16diameter but axes not visually verified after503; these are not adopted as geometry.; Gold-platedNYS322G andgold-shellNYS322AG variants stay separate; no MIDI circuit map from physical5pin form.
Manufacturer	REAN (NYS322)S617Named source examples retain separate role, part, view and axis limits; values are not a universal family specification. NYS322. Documented role: plug. 6.5mmmaximum cableOD is wire acceptance,not shell diameter.; NYS322drawingS618full text provides59.5,13.35diameter,16diameter but axes not visually verified after503; these are not adopted as geometry.; Gold-platedNYS322G andgold-shellNYS322AG variants stay separate; no MIDI circuit map from physical5pin form.
Series	NYS322 DIN (NYS322)S617Named source examples retain separate role, part, view and axis limits; values are not a universal family specification. NYS322. Documented role: plug. 6.5mmmaximum cableOD is wire acceptance,not shell diameter.; NYS322drawingS618full text provides59.5,13.35diameter,16diameter but axes not visually verified after503; these are not adopted as geometry.; Gold-platedNYS322G andgold-shellNYS322AG variants stay separate; no MIDI circuit map from physical5pin form.
Exact part / implementation	NYS322 (NYS322)S617Named source examples retain separate role, part, view and axis limits; values are not a universal family specification. NYS322. Documented role: plug. 6.5mmmaximum cableOD is wire acceptance,not shell diameter.; NYS322drawingS618full text provides59.5,13.35diameter,16diameter but axes not visually verified after503; these are not adopted as geometry.; Gold-platedNYS322G andgold-shellNYS322AG variants stay separate; no MIDI circuit map from physical5pin form.

Not recorded: Positions / cavity span, Populated contacts, Contact rows, Contact pitch, Dimensions / axis, Contact gender / arrangement, Mounting, Coupling / latch, Keying / polarization, Shell / form, Recorded markings, View convention. Unknown fields stay unknown; illustrations supply no measurements or pin assignments.

Recorded variant and source limits

Check the exact device manual before wiring or applying power.
MIDI 1.0 OUT (and optional THRU) jack, 5-pin 180-degree DIN female, CA-033: Pin numbers as drawn in CA-033 Figures 1-2 (DIN numbering 1-3-5-2-4 arc); the figures are schematic, not a dimensioned face view.
MIDI 1.0 IN jack, 5-pin 180-degree DIN female, CA-033: As for midi-out-thru.
IBM Personal Computer AT keyboard connector (system board J22) and keyboard cable DIN: IBM states pin numbering is shown in the Keyboard section; this pass relied on the text tables only, so no spatial face view is asserted.
MIDI 1.0 OUT jack (MMA CA-033): Use DIN contact numbers 1-5 (180-degree layout). Spatial positions are not transferred from any figure; MIDI device jacks are female, cables male (CA-033 p. 3).
MIDI 1.0 IN jack (MMA CA-033): Use DIN contact numbers 1-5 (180-degree layout). Spatial positions are not transferred from any figure; MIDI device jacks are female, cables male (CA-033 p. 3).
MIDI 1.0 THRU jack, optional (MMA CA-033): Use DIN contact numbers 1-5 (180-degree layout). Spatial positions are not transferred from any figure; MIDI device jacks are female, cables male (CA-033 p. 3).
IBM Personal Computer AT keyboard connector J22 (system board) / keyboard cable DIN end: Use DIN contact numbers 1-5 (180-degree layout). Spatial positions are not transferred from any figure; MIDI device jacks are female, cables male (CA-033 p. 3).
PC AT keyboard 5-pin DIN as tabulated in Atmel AVR313: Use DIN contact numbers 1-5 (180-degree layout). Spatial positions are not transferred from any figure; MIDI device jacks are female, cables male (CA-033 p. 3).

Report a correction to these facts →

Pins & wiring

Pinout

Choose the exact wiring. Pin numbers follow its stated view; a schematic does not establish physical positions. Check your exact device before wiring.

Dark pinout view

What the status labels mean

Confirmed: Recorded research passes agree within this variant; this is not independent human review or hardware validation.
Single source: Only one underlying document, or one pass, supports this assignment.
Device-specific: Supported for the named equipment or wiring only. Check your device’s manual.
Unverified: Missing or conflicting evidence. Do not wire from this row.
Not connected: The source explicitly says NC, no contact or no pin for this wiring.

Wiring variantMIDI 1.0 OUT (and optional THRU) jack, 5-pin 180-degree DIN female, …

MIDI 1.0 OUT (and optional THRU) jack, 5-pin 180-degree DIN female, CA-033

View and evidence limits

Pin numbers as drawn in CA-033 Figures 1-2 (DIN numbering 1-3-5-2-4 arc); the figures are schematic, not a dimensioned face view.

P110 5-pin DIN — **Agree** on MIDI OUT/THRU (2 shield, 4 current source, 5 data; 1 and 3 N/C), MIDI IN (4 and 5 loop to opto-isolator, 2 shield with no ground path) and IBM PC AT keyboard (1 clock, 2 data, 3 reserved, 4 ground, 5 +5 V) — Both used MIDI Association CA-033 and the IBM AT Technical Reference. B adds Atmel AVR313 as a second keyboard source.
THRU uses the same pin roles as OUT (Figure 2 optional THRU circuit: pin 4 via RE from VTX, pin 5 via RF from the buffered receiver data, pin 2 to ground, pins 1/3 N/C).
Jack shield (shell) may be N/C or grounded for EMI/EMC; it is not a numbered pin.
The IBM PC and PC/XT technical references were not retrieved; the XT-era use of pin 3 was not established.
No primary document for DIN audio, tape-recorder or other 5-pin DIN uses was retrieved.
Superseded by CA-033 for hardware; the original edition was not separately checked.

Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.

MIDI 1.0 OUT (and optional THRU) jack, 5-pin 180-degree DIN female, CA-033 — source-scoped contact map
Pin	Signal	What it does	Status
1	N/C	Not connected or absent in this named wiring.	Not connected Sources
2	Shield / ground	Cable screen or shield connection; check the named equipment.	Single source Sources
3	N/C	Not connected or absent in this named wiring.	Not connected Sources
4	Current source (VTX via RA)	Signal conductor. Pair, polarity and direction follow this named wiring.	Single source Sources
5	Data (UART TX via RC)	Signal conductor. Pair, polarity and direction follow this named wiring.	Single source Sources

Sources (1)

S729 · MIDI Manufacturers Association / AMEI (published by The MIDI Association) · (CA-033) MIDI 1.0 Electrical Specification Update [2014]
CA# 033; issue date Aug 1 2014; MMA approval Jan 20 2014 | Issue date Aug 1 2014; MMA approval Jan 20 2014; replaces Hardware section of MIDI 1.0 Detailed Specification v4.2 · p. 2, Figure 1 'MIDI OUT Circuit' and side notes ('Pin 2 must be tied to ground on the MIDI transmitter only'); p. 3, 'MIDI Device Connectors' text ('Note that pins 1 and 3 are not used, and should be left unconnected in the receiver and transmitter'); pp. 3-4, 'MIDI Cable' text and Figure 3 (shield connected only to pin 2 at both ends)

MIDI 1.0 IN jack, 5-pin 180-degree DIN female, CA-033

View and evidence limits

As for midi-out-thru.

P110 5-pin DIN — **Agree** on MIDI OUT/THRU (2 shield, 4 current source, 5 data; 1 and 3 N/C), MIDI IN (4 and 5 loop to opto-isolator, 2 shield with no ground path) and IBM PC AT keyboard (1 clock, 2 data, 3 reserved, 4 ground, 5 +5 V) — Both used MIDI Association CA-033 and the IBM AT Technical Reference. B adds Atmel AVR313 as a second keyboard source.
'Do not connect any pins of the MIDI IN jack directly to ground.' Jack shield: N/C or optional 0.1 uF capacitor to ground.
The IBM PC and PC/XT technical references were not retrieved; the XT-era use of pin 3 was not established.
No primary document for DIN audio, tape-recorder or other 5-pin DIN uses was retrieved.
Superseded by CA-033 for hardware; the original edition was not separately checked.

Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.

MIDI 1.0 IN jack, 5-pin 180-degree DIN female, CA-033 — source-scoped contact map
Pin	Signal	What it does	Status
1	N/C	Not connected or absent in this named wiring.	Not connected Sources
2	Shield (no DC ground)	Cable screen or shield connection; check the named equipment.	Single source Sources
3	N/C	Not connected or absent in this named wiring.	Not connected Sources
4	Current loop (to opto-isolator via RB)	Control, detection or configuration connection; check the source and device.	Single source Sources
5	Current loop return (opto-isolator)	Control, detection or configuration connection; check the source and device.	Single source Sources

Sources (1)

S729 · MIDI Manufacturers Association / AMEI (published by The MIDI Association) · (CA-033) MIDI 1.0 Electrical Specification Update [2014]
CA# 033; issue date Aug 1 2014; MMA approval Jan 20 2014 | Issue date Aug 1 2014; MMA approval Jan 20 2014; replaces Hardware section of MIDI 1.0 Detailed Specification v4.2 · p. 3, Figure 2 'MIDI IN and THRU circuit'; p. 3, 'MIDI Device Connectors' text ('Note that pins 1 and 3 are not used, and should be left unconnected in the receiver and transmitter')

IBM Personal Computer AT keyboard connector (system board J22) and k…

IBM Personal Computer AT keyboard connector (system board J22) and keyboard cable DIN

Device-specific wiring. Check your device’s manual before connecting or applying power.

View and evidence limits

IBM states pin numbering is shown in the Keyboard section; this pass relied on the text tables only, so no spatial face view is asserted.

P110 5-pin DIN — **Agree** on MIDI OUT/THRU (2 shield, 4 current source, 5 data; 1 and 3 N/C), MIDI IN (4 and 5 loop to opto-isolator, 2 shield with no ground path) and IBM PC AT keyboard (1 clock, 2 data, 3 reserved, 4 ground, 5 +5 V) — Both used MIDI Association CA-033 and the IBM AT Technical Reference. B adds Atmel AVR313 as a second keyboard source.
J22 is described as a '5-pin, 90-degree Printed Circuit Board (PCB) mounting, DIN connector' (90-degree refers to the right-angle PCB mount).
101/102-key cable table (p. 4-37) also maps cable shield to frame ground on the SDL end; that is not a DIN pin.
The IBM PC and PC/XT technical references were not retrieved; the XT-era use of pin 3 was not established.
No primary document for DIN audio, tape-recorder or other 5-pin DIN uses was retrieved.
Superseded by CA-033 for hardware; the original edition was not separately checked.

Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.

IBM Personal Computer AT keyboard connector (system board J22) and keyboard cable DIN — source-scoped contact map
Pin	Signal	What it does	Status
1	Keyboard Clock (+KBD CLK)	Clock or clock-control connection, as named by this source.	Device-specific Sources
2	Keyboard Data (+KBD DATA)	Signal conductor. Pair, polarity and direction follow this named wiring.	Device-specific Sources
3	Reserved	Reserved; no general-purpose wiring is established.	Device-specific Sources
4	Ground	Ground reference and return.	Device-specific Sources
5	+5 Vdc	Power connection (+5 Vdc). Check the specified supply.	Device-specific Sources

Sources (1)

S730 · IBM · Personal Computer AT Technical Reference (6183355)
Revised Edition (March 1986) · System Board section, printed p. 1-73, 'Keyboard Connector (J22)' pin assignment table; 84-Key Keyboard section, printed p. 4-5, 'Cabling' DIN Connector Pins table; 101/102-Key Keyboard section, printed p. 4-37, 'Cabling' table (DIN pins vs SDL pins)

MIDI 1.0 OUT jack (MMA CA-033)

View and evidence limits

Use DIN contact numbers 1-5 (180-degree layout). Spatial positions are not transferred from any figure; MIDI device jacks are female, cables male (CA-033 p. 3).

P110 5-pin DIN — **Agree** on MIDI OUT/THRU (2 shield, 4 current source, 5 data; 1 and 3 N/C), MIDI IN (4 and 5 loop to opto-isolator, 2 shield with no ground path) and IBM PC AT keyboard (1 clock, 2 data, 3 reserved, 4 ground, 5 +5 V) — Both used MIDI Association CA-033 and the IBM AT Technical Reference. B adds Atmel AVR313 as a second keyboard source.
Legacy domestic-audio 5-pin DIN wiring (record/playback, stereo) was not established from a primary document; the standards are paywalled and no manufacturer manual was read.
CA-033 defines roles by circuit figures, not by text names such as 'source'/'sink'; signal names above are descriptive paraphrases of Figures 1 and 2.
Other proprietary uses (e.g. synthesiser sync, DC power, older video) were not researched.

Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.

MIDI 1.0 OUT jack (MMA CA-033) — source-scoped contact map
Pin	Signal	What it does	Status
1	N/C	Not connected or absent in this named wiring.	Not connected Sources
2	Ground / shield	Cable screen or shield connection; check the named equipment.	Single source Sources
3	N/C	Not connected or absent in this named wiring.	Not connected Sources
4	Current source (via RA to VTX)	Signal conductor. Pair, polarity and direction follow this named wiring.	Single source Sources
5	Data / current sink (via RC from UART)	Signal conductor. Pair, polarity and direction follow this named wiring.	Single source Sources

Sources (1)

S729 · MIDI Manufacturers Association / AMEI (published by The MIDI Association) · (CA-033) MIDI 1.0 Electrical Specification Update [2014]
CA# 033; issue date Aug 1 2014; MMA approval Jan 20 2014 | Issue date Aug 1 2014; MMA approval Jan 20 2014; replaces Hardware section of MIDI 1.0 Detailed Specification v4.2 · p. 2, Figure 1 'MIDI OUT Circuit' and side notes ('Pin 2 must be tied to ground on the MIDI transmitter only'); p. 3, 'MIDI Device Connectors' (pins 1 and 3 not used; shield options)

MIDI 1.0 IN jack (MMA CA-033)

View and evidence limits

Use DIN contact numbers 1-5 (180-degree layout). Spatial positions are not transferred from any figure; MIDI device jacks are female, cables male (CA-033 p. 3).

P110 5-pin DIN — **Agree** on MIDI OUT/THRU (2 shield, 4 current source, 5 data; 1 and 3 N/C), MIDI IN (4 and 5 loop to opto-isolator, 2 shield with no ground path) and IBM PC AT keyboard (1 clock, 2 data, 3 reserved, 4 ground, 5 +5 V) — Both used MIDI Association CA-033 and the IBM AT Technical Reference. B adds Atmel AVR313 as a second keyboard source.
Legacy domestic-audio 5-pin DIN wiring (record/playback, stereo) was not established from a primary document; the standards are paywalled and no manufacturer manual was read.
CA-033 defines roles by circuit figures, not by text names such as 'source'/'sink'; signal names above are descriptive paraphrases of Figures 1 and 2.
Other proprietary uses (e.g. synthesiser sync, DC power, older video) were not researched.

Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.

MIDI 1.0 IN jack (MMA CA-033) — source-scoped contact map
Pin	Signal	What it does	Status
1	N/C	Not connected or absent in this named wiring.	Not connected Sources
2	Shield (no DC path to ground)	Cable screen or shield connection; check the named equipment.	Single source Sources
3	N/C	Not connected or absent in this named wiring.	Not connected Sources
4	Loop input to opto-isolator (via RB 220 ohm)	Control, detection or configuration connection; check the source and device.	Single source Sources
5	Loop return from opto-isolator	Control, detection or configuration connection; check the source and device.	Single source Sources

Sources (1)

S729 · MIDI Manufacturers Association / AMEI (published by The MIDI Association) · (CA-033) MIDI 1.0 Electrical Specification Update [2014]
CA# 033; issue date Aug 1 2014; MMA approval Jan 20 2014 | Issue date Aug 1 2014; MMA approval Jan 20 2014; replaces Hardware section of MIDI 1.0 Detailed Specification v4.2 · p. 3, Figure 2 'MIDI IN and THRU circuit' (IN half) and 'MIDI Device Connectors' text

MIDI 1.0 THRU jack, optional (MMA CA-033)

View and evidence limits

Use DIN contact numbers 1-5 (180-degree layout). Spatial positions are not transferred from any figure; MIDI device jacks are female, cables male (CA-033 p. 3).

P110 5-pin DIN — **Agree** on MIDI OUT/THRU (2 shield, 4 current source, 5 data; 1 and 3 N/C), MIDI IN (4 and 5 loop to opto-isolator, 2 shield with no ground path) and IBM PC AT keyboard (1 clock, 2 data, 3 reserved, 4 ground, 5 +5 V) — Both used MIDI Association CA-033 and the IBM AT Technical Reference. B adds Atmel AVR313 as a second keyboard source.
Legacy domestic-audio 5-pin DIN wiring (record/playback, stereo) was not established from a primary document; the standards are paywalled and no manufacturer manual was read.
CA-033 defines roles by circuit figures, not by text names such as 'source'/'sink'; signal names above are descriptive paraphrases of Figures 1 and 2.
Other proprietary uses (e.g. synthesiser sync, DC power, older video) were not researched.

Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.

MIDI 1.0 THRU jack, optional (MMA CA-033) — source-scoped contact map
Pin	Signal	What it does	Status
1	N/C	Not connected or absent in this named wiring.	Not connected Sources
2	Ground / shield	Cable screen or shield connection; check the named equipment.	Single source Sources
3	N/C	Not connected or absent in this named wiring.	Not connected Sources
4	Current source (via RE to VTX)	Signal conductor. Pair, polarity and direction follow this named wiring.	Single source Sources
5	Data / current sink (via RF from buffer)	Signal conductor. Pair, polarity and direction follow this named wiring.	Single source Sources

Sources (1)

S729 · MIDI Manufacturers Association / AMEI (published by The MIDI Association) · (CA-033) MIDI 1.0 Electrical Specification Update [2014]
CA# 033; issue date Aug 1 2014; MMA approval Jan 20 2014 | Issue date Aug 1 2014; MMA approval Jan 20 2014; replaces Hardware section of MIDI 1.0 Detailed Specification v4.2 · p. 3, Figure 2 'MIDI IN and THRU circuit', Optional MIDI Thru Circuit (RE to pin 4, RF to pin 5, pin 2 to ground)

IBM Personal Computer AT keyboard connector J22 (system board) / key…

IBM Personal Computer AT keyboard connector J22 (system board) / keyboard cable DIN end

Device-specific wiring. Check your device’s manual before connecting or applying power.

View and evidence limits

IBM PC AT J22 and keyboard cable DIN contact numbers1-5 only. Spatial positions are not established by this table-only normalization; MIDI female-jack wording does not apply to this keyboard connector.

P110 5-pin DIN — **Agree** on MIDI OUT/THRU (2 shield, 4 current source, 5 data; 1 and 3 N/C), MIDI IN (4 and 5 loop to opto-isolator, 2 shield with no ground path) and IBM PC AT keyboard (1 clock, 2 data, 3 reserved, 4 ground, 5 +5 V) — Both used MIDI Association CA-033 and the IBM AT Technical Reference. B adds Atmel AVR313 as a second keyboard source.
Legacy domestic-audio 5-pin DIN wiring (record/playback, stereo) was not established from a primary document; the standards are paywalled and no manufacturer manual was read.
CA-033 defines roles by circuit figures, not by text names such as 'source'/'sink'; signal names above are descriptive paraphrases of Figures 1 and 2.
Other proprietary uses (e.g. synthesiser sync, DC power, older video) were not researched.

Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.

IBM Personal Computer AT keyboard connector J22 (system board) / keyboard cable DIN end — source-scoped contact map
Pin	Signal	What it does	Status
1	Keyboard Clock (+KBD CLK)	Clock or clock-control connection, as named by this source.	Device-specific Sources
2	Keyboard Data (+KBD DATA)	Signal conductor. Pair, polarity and direction follow this named wiring.	Device-specific Sources
3	Reserved	Reserved; no general-purpose wiring is established.	Device-specific Sources
4	Ground	Ground reference and return.	Device-specific Sources
5	+5 Vdc	Power connection (+5 Vdc). Check the specified supply.	Device-specific Sources

Sources (1)

S731 · IBM · Technical Reference, Personal Computer AT
Revised Edition (March 1986), part 6183355 · Section 1 System Board, 'Keyboard Connector (J22)' table; Section 4, 84-Key Keyboard, 'Cabling', DIN Connector Pins table; Section 4, 101/102-Key Keyboard, 'Cabling' table (DIN pins vs SDL pins)

PC AT keyboard 5-pin DIN as tabulated in Atmel AVR313

View and evidence limits

Atmel AVR313 PC AT keyboard DIN contact numbers1-5 only. Spatial positions and equipment connector gender are not established here; MIDI female-jack wording does not apply.

P110 5-pin DIN — **Agree** on MIDI OUT/THRU (2 shield, 4 current source, 5 data; 1 and 3 N/C), MIDI IN (4 and 5 loop to opto-isolator, 2 shield with no ground path) and IBM PC AT keyboard (1 clock, 2 data, 3 reserved, 4 ground, 5 +5 V) — Both used MIDI Association CA-033 and the IBM AT Technical Reference. B adds Atmel AVR313 as a second keyboard source.
Legacy domestic-audio 5-pin DIN wiring (record/playback, stereo) was not established from a primary document; the standards are paywalled and no manufacturer manual was read.
CA-033 defines roles by circuit figures, not by text names such as 'source'/'sink'; signal names above are descriptive paraphrases of Figures 1 and 2.
Other proprietary uses (e.g. synthesiser sync, DC power, older video) were not researched.

Schematic only · physical contact positions unconfirmed. Original drawing · not to scale. Scroll sideways if needed.

PC AT keyboard 5-pin DIN as tabulated in Atmel AVR313 — source-scoped contact map
Pin	Signal	What it does	Status
1	Clock	Clock or clock-control connection, as named by this source.	Single source Sources
2	Data	Signal conductor. Pair, polarity and direction follow this named wiring.	Single source Sources
3	nc	Not connected or absent in this named wiring.	Not connected Sources
4	GND	Ground reference and return.	Single source Sources
5	+5V	Power connection (+5V). Check the specified supply.	Single source Sources

Sources (1)

S724 · Atmel (now Microchip Technology) · AVR313: Interfacing the PC AT Keyboard (application note)
Rev. 1235B-AVR-05/02 · p. 2, Table 1 'AT Keyboard Connector Pin Assignments', column 'DIN41524, Female at Computer, 5-pin DIN 180 degrees'

Unknowns stay unknown.

Check the exact device manual before wiring or applying power.

Your next step

Use the detail without guessing past its limits.

Read the connector field note Recognition clues and practical checks.Work through a connection Keep exact equipment and cable requirements separate.

Source trail

Claims and sources

C803Ysource checked

MIDI 1.0 OUT (and optional THRU) jack, 5-pin 180-degree DIN female, CA-033: original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

MIDI Manufacturers Association / AMEI (published by The MIDI Association) · (CA-033) MIDI 1.0 Electrical Specification Update [2014] ↗
p. 2, Figure 1 'MIDI OUT Circuit' and side notes ('Pin 2 must be tied to ground on the MIDI transmitter only'); p. 3, 'MIDI Device Connectors' (pins 1 and 3 not used; shield options); p. 3, 'MIDI Device Connectors' text ('Note that pins 1 and 3 are not used, and should be left unconnected in the receiver and transmitter'); p. 3, Figure 2 'MIDI IN and THRU circuit'; p. 3, Figure 2 'MIDI IN and THRU circuit' (IN half) and 'MIDI Device Connectors' text; p. 3, Figure 2 'MIDI IN and THRU circuit', Optional MIDI Thru Circuit (RE to pin 4, RF to pin 5, pin 2 to ground); pp. 3-4, 'MIDI Cable' text and Figure 3 (shield connected only to pin 2 at both ends) · Source scope and unresolved evidence are preserved in the engineering variant.

C803Zsource checked

MIDI 1.0 IN jack, 5-pin 180-degree DIN female, CA-033: original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

C804Asource checked

IBM Personal Computer AT keyboard connector (system board J22) and keyboard cable DIN: original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

IBM · Personal Computer AT Technical Reference (6183355) ↗
101/102-Key Keyboard section, printed p. 4-37, 'Cabling' table (DIN pins vs SDL pins); 84-Key Keyboard section, printed p. 4-5, 'Cabling' DIN Connector Pins table; System Board section, printed p. 1-73, 'Keyboard Connector (J22)' pin assignment table · Source scope and unresolved evidence are preserved in the engineering variant.

C804Bsource checked

MIDI 1.0 OUT jack (MMA CA-033): original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

C804Csource checked

MIDI 1.0 IN jack (MMA CA-033): original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

C804Dsource checked

MIDI 1.0 THRU jack, optional (MMA CA-033): original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

C804Esource checked

IBM Personal Computer AT keyboard connector J22 (system board) / keyboard cable DIN end: original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

IBM · Technical Reference, Personal Computer AT ↗
Section 1 System Board, 'Keyboard Connector (J22)' table; Section 4, 101/102-Key Keyboard, 'Cabling' table (DIN pins vs SDL pins); Section 4, 84-Key Keyboard, 'Cabling', DIN Connector Pins table · Source scope and unresolved evidence are preserved in the engineering variant.

C804Fsource checked

PC AT keyboard 5-pin DIN as tabulated in Atmel AVR313: original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

Atmel (now Microchip Technology) · AVR313: Interfacing the PC AT Keyboard (application note) ↗
p. 2, Table 1 'AT Keyboard Connector Pin Assignments', column 'DIN41524, Female at Computer, 5-pin DIN 180 degrees'; p. 2, Table 1, column '6-pin Mini DIN PS2 Style Female at Computer' · Source scope and unresolved evidence are preserved in the engineering variant.

4 source records support this profile. No independent engineering review or hardware validation is claimed.

Evidence behind this page

Scope first. Source second. Approval separate.

4 linked sources · 8 scoped claims · 0 sources with inspection/access flags.

Page scope: Original schematic; not to scale and not fabrication approval.

Assessment 2026-10-22 · earliest scheduled source review 2027-01-18. This is a recorded-date assessment, not a live source check. Page-level independent review is not established by this panel.

Inspect 4 source scopes, access limits and dates

S724 · AVR313: Interfacing the PC AT Keyboard (application note)

Atmel (now Microchip Technology) · Manufacturer / product-owner domain · inspected 2026-10-21 · due 2027-01-19

Within inspection window

Scoped support: Exact named pinout variant only; not capability or compatibility approval.

Not established / limitations: Source scope and unresolved evidence are preserved in the engineering variant.

Locator: p. 2, Table 1 'AT Keyboard Connector Pin Assignments', column 'DIN41524, Female at Computer, 5-pin DIN 180 degrees'; p. 2, Table 1, column '6-pin Mini DIN PS2 Style Female at Computer'

S729 · (CA-033) MIDI 1.0 Electrical Specification Update [2014]

MIDI Manufacturers Association / AMEI (published by The MIDI Association) · Standards-organization domain · inspected 2026-10-20 · due 2027-01-18

Within inspection window

Scoped support: Exact named pinout variant only; not capability or compatibility approval.

Not established / limitations: Source scope and unresolved evidence are preserved in the engineering variant.

Locator: p. 2, Figure 1 'MIDI OUT Circuit' and side notes ('Pin 2 must be tied to ground on the MIDI transmitter only'); p. 3, 'MIDI Device Connectors' (pins 1 and 3 not used; shield options); p. 3, 'MIDI Device Connectors' text ('Note that pins 1 and 3 are not used, and should be left unconnected in the receiver and transmitter'); p. 3, Figure 2 'MIDI IN and THRU circuit'; p. 3, Figure 2 'MIDI IN and THRU circuit' (IN half) and 'MIDI Device Connectors' text; p. 3, Figure 2 'MIDI IN and THRU circuit', Optional MIDI Thru Circuit (RE to pin 4, RF to pin 5, pin 2 to ground); pp. 3-4, 'MIDI Cable' text and Figure 3 (shield connected only to pin 2 at both ends)

S730 · Personal Computer AT Technical Reference (6183355)

IBM · Unclassified publisher domain · inspected 2026-10-20 · due 2027-01-18

Within inspection window

Scoped support: Exact named pinout variant only; not capability or compatibility approval.

Not established / limitations: Source scope and unresolved evidence are preserved in the engineering variant.

Locator: 101/102-Key Keyboard section, printed p. 4-37, 'Cabling' table (DIN pins vs SDL pins); 84-Key Keyboard section, printed p. 4-5, 'Cabling' DIN Connector Pins table; System Board section, printed p. 1-73, 'Keyboard Connector (J22)' pin assignment table

S731 · Technical Reference, Personal Computer AT

IBM · Unclassified publisher domain · inspected 2026-10-21 · due 2027-01-19

Within inspection window

Scoped support: Exact named pinout variant only; not capability or compatibility approval.

Not established / limitations: Source scope and unresolved evidence are preserved in the engineering variant.

Locator: Section 1 System Board, 'Keyboard Connector (J22)' table; Section 4, 101/102-Key Keyboard, 'Cabling' table (DIN pins vs SDL pins); Section 4, 84-Key Keyboard, 'Cabling', DIN Connector Pins table

Trace 8 claims to their source records

C803Y · P110

MIDI 1.0 OUT (and optional THRU) jack, 5-pin 180-degree DIN female, CA-033: original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

Claim scope: Pinout variant only; see comparison and per-contact status. Not fabrication approval.

Source links: S729 · Evidence trail → (private workspace)

C803Z · P110

MIDI 1.0 IN jack, 5-pin 180-degree DIN female, CA-033: original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

Claim scope: Pinout variant only; see comparison and per-contact status. Not fabrication approval.

Source links: S729 · Evidence trail → (private workspace)

C804A · P110

Claim scope: Pinout variant only; see comparison and per-contact status. Not fabrication approval.

Source links: S730 · Evidence trail → (private workspace)

C804B · P110

MIDI 1.0 OUT jack (MMA CA-033): original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

Claim scope: Pinout variant only; see comparison and per-contact status. Not fabrication approval.

Source links: S729 · Evidence trail → (private workspace)

C804C · P110

MIDI 1.0 IN jack (MMA CA-033): original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

Claim scope: Pinout variant only; see comparison and per-contact status. Not fabrication approval.

Source links: S729 · Evidence trail → (private workspace)

C804D · P110

MIDI 1.0 THRU jack, optional (MMA CA-033): original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

Claim scope: Pinout variant only; see comparison and per-contact status. Not fabrication approval.

Source links: S729 · Evidence trail → (private workspace)

C804E · P110

Claim scope: Pinout variant only; see comparison and per-contact status. Not fabrication approval.

Source links: S731 · Evidence trail → (private workspace)

C804F · P110

PC AT keyboard 5-pin DIN as tabulated in Atmel AVR313: original contact normalization. Statuses distinguish comparison agreement, source limits and named-device wiring.

Claim scope: Pinout variant only; see comparison and per-contact status. Not fabrication approval.

Source links: S724 · Evidence trail → (private workspace)

Prepare this page for review →Read the evidence method →

Recorded evidence only. An inspection date, publisher label, source link or generated packet is not independent technical review, hardware testing, fabrication approval or a compatibility verdict.