GPIB emulator for HP85 disk emulator project for AVR. More...

#include "user_config.h"
#include "hal.h"
#include "gpib_hal.h"
#include "posix.h"

Macros
#define	GPIB_BUS_SETTLE_DELAY 2

#define	HTIMEOUT (500000L / GPIB_TASK_TIC_US)
	This is the default BUS timeout of 0.5 Seconds in Microseconds. More...

#define	EOI_FLAG 0x0100
	bus flags More...

#define	SRQ_FLAG 0x0200

#define	ATN_FLAG 0x0400

#define	REN_FLAG 0x0800

#define	IFC_FLAG 0x1000

#define	PP_FLAG 0x2000
	BUS state flags. More...

#define	TIMEOUT_FLAG 0x4000

#define	BUS_ERROR_FLAG 0x8000

#define	DAV_FLAG 0x2000
	handshake flasg used in tracing More...

#define	NRFD_FLAG 0x4000

#define	NDAC_FLAG 0x8000

#define	ERROR_MASK (IFC_FLAG \| TIMEOUT_FLAG \| BUS_ERROR_FLAG)

#define	CONTROL_MASK (EOI_FLAG \| SRQ_FLAG \| ATN_FLAG \| REN_FLAG)

#define	DATA_MASK 0x00ff

#define	CMD_MASK 0x007f

#define	STATUS_MASK 0xff00

#define	TRACE_ALL 1 /* trace all bus states durring a read */
	arguments to gpib_read_byte More...

#define	NO_TRACE 0 /* do not trace bus states durring a read */

#define	GPIB_IOBUFF_LEN 512 /* Max length of RX/TX GPIB string */

Enumerations
enum	{ TRACE_DISABLE, TRACE_READ, TRACE_BUS }
	GPIB read trace states. More...

enum	{ GPIB_RX_START = 0, GPIB_RX_WAIT_FOR_DAV_LOW, GPIB_RX_DAV_IS_LOW, GPIB_RX_WAIT_FOR_NDAC_HI, GPIB_RX_WAIT_FOR_DAV_HI, GPIB_RX_DAV_IS_HI, GPIB_RX_FINISH, GPIB_RX_ERROR, GPIB_RX_DONE }

enum	{ GPIB_TX_START = 0, GPIB_TX_WAIT_FOR_NRFD_OR_NDAC_LOW, GPIB_TX_PUT_DATA, GPIB_TX_WAIT_FOR_NRFD_HI, GPIB_TX_SET_DAV_LOW, GPIB_TX_WAIT_FOR_NDAC_HI, GPIB_TX_SET_DAV_HI, GPIB_TX_FINISH, GPIB_TX_ERROR, GPIB_TX_DONE }

enum	{ GPIB_PP_IDLE = 0, GPIB_PP_DETECTED }

Functions
void	gpib_timer_elapsed_begin (void)
	Start measuring time - used with hpib_timer_elapsed_end() More...

void	gpib_timer_reset (void)
	Reset elapsed and timeout timers Elapses and Timeout Timers. More...

void	gpib_timer_elapsed_end (char *msg)
	Display user message and time delta since gpib_timer_elapsed_begin() call. More...

void	gpib_timer_task (void)
	Main GPIB timer task called by low level interrup hander. More...

void	gpib_timeout_set (uint32_t time)
	Set GPIB timeout timer in units of GPIB_TASK_TIC_US. More...

uint8_t	gpib_timeout_test (void)
	Test GPIB timeout timer for timeout condition. More...

void	gpib_bus_init (void)
	Initialize/Release GPIB Bus control lines Used for Power ON, Reset or IFC LOW reset conditions. More...

void	gpib_rx_init (uint8_t busy)
	Initialize GPIB Bus control lines for READ. More...

void	gpib_tx_init (void)
	Initialize GPIB Bus control lines for WRITE. More...

void	gpib_state_init (void)
	Reset GPIB states and related variables. More...

void	gpib_enable_PPR (int bit)

void	gpib_disable_PPR (int bit)
	Disable PPR (Parallel Poll Response) for a device. More...

uint8_t	gpib_detect_PP (void)
	Attempt to detect the Parallel Poll Reposnse state Used only for debugging - it is unlikely that we will catch this state V2 hardware - this does not work unless reading BUS. More...

uint16_t	gpib_unread (uint16_t ch)
	GPIB ungets one character and all status states. More...

uint8_t	gpib_bus_read (void)
	Read GPIB data BUS only. More...

uint16_t	gpib_control_pin_read (void)
	Read GPIB control lines only FIXME V2 boards can only read pins enabled for read by the SN75162 FIXME We could add a test for read/write state ?? More...

uint16_t	gpib_handshake_pin_read (void)
	Read GPIB handshake lines only FIXME: V2 boards can only read pins enabled for read by the SN75162 FIXME We could add a test for read/write state ?? More...

uint16_t	gpib_write_byte (uint16_t ch)
	Send 1 byte and control line states to GPIB BUS. More...

uint16_t	gpib_read_byte (int trace)
	read 1 byte and control line status from GPIB BUS More...

void	gpib_decode_header (FILE *fo)
	Displays help for gpib_decode() function. More...

void	gpib_trace_display (uint16_t status, int trace_state)
	decode/display all control flags and data on the GPIB BUS More...

void	gpib_decode (uint16_t ch)
	Calls gpib_decode_str() and dosplays the result. More...

int	gpib_read_str (uint8_t buf, int size, uint16_t status)
	Read string from GPIB BUS - controlled by status flags. More...

int	gpib_write_str (uint8_t buf, int size, uint16_t status)
	Send string to GPIB BUS - controlled by status flags. More...

Variables
uint8_t	gpib_iobuff [GPIB_IOBUFF_LEN]
	common IO buffer for gpib_read_str() and gpib_write_str() More...

int	debuglevel
	Debug flag - used to log GPIB and emulator messages. More...

uint8_t	talk31

uint8_t	talking
	gpib talk address More...

uint8_t	talking_last
	gpib last talk address More...

uint8_t	listening
	gpib listen address More...

uint8_t	listening_last
	gpib last listen address More...

uint8_t	spoll
	gpib serial poll status More...

uint16_t	current

uint16_t	lastcmd

uint8_t	secondary
	gpib secondary More...

uint8_t	device

Detailed Description

GPIB emulator for HP85 disk emulator project for AVR.

Edit History

[1.0] [Mike Gore] Initial revision of file.

Copyright © 2014-2020 Mike Gore, All rights reserved. GPL

See also: http://github.com/magore/hp85disk; http://github.com/magore/hp85disk/COPYRIGHT.md for Copyright details

Based on work by Anders Gustafsson.

Copyright © 2014 Anders Gustafsson All rights reserved..

Definition in file gpib.h.

Macro Definition Documentation

◆ ATN_FLAG

#define ATN_FLAG 0x0400

Definition at line 35 of file gpib.h.

◆ BUS_ERROR_FLAG

#define BUS_ERROR_FLAG 0x8000

Definition at line 42 of file gpib.h.

◆ CMD_MASK

#define CMD_MASK 0x007f

Definition at line 53 of file gpib.h.

◆ CONTROL_MASK

#define CONTROL_MASK (EOI_FLAG | SRQ_FLAG | ATN_FLAG | REN_FLAG)

Definition at line 50 of file gpib.h.

◆ DATA_MASK

#define DATA_MASK 0x00ff

Definition at line 52 of file gpib.h.

◆ DAV_FLAG

#define DAV_FLAG 0x2000

handshake flasg used in tracing

Definition at line 45 of file gpib.h.

◆ EOI_FLAG

#define EOI_FLAG 0x0100

bus flags

Definition at line 33 of file gpib.h.

◆ ERROR_MASK

#define ERROR_MASK (IFC_FLAG | TIMEOUT_FLAG | BUS_ERROR_FLAG)

Definition at line 49 of file gpib.h.

◆ GPIB_BUS_SETTLE_DELAY

#define GPIB_BUS_SETTLE_DELAY 2

Definition at line 27 of file gpib.h.

◆ GPIB_IOBUFF_LEN

#define GPIB_IOBUFF_LEN 512 /* Max length of RX/TX GPIB string */

Definition at line 101 of file gpib.h.

◆ HTIMEOUT

#define HTIMEOUT (500000L / GPIB_TASK_TIC_US)

This is the default BUS timeout of 0.5 Seconds in Microseconds.

Definition at line 30 of file gpib.h.

◆ IFC_FLAG

#define IFC_FLAG 0x1000

Definition at line 37 of file gpib.h.

◆ NDAC_FLAG

#define NDAC_FLAG 0x8000

Definition at line 47 of file gpib.h.

◆ NO_TRACE

#define NO_TRACE 0 /* do not trace bus states durring a read */

Definition at line 66 of file gpib.h.

◆ NRFD_FLAG

#define NRFD_FLAG 0x4000

Definition at line 46 of file gpib.h.

◆ PP_FLAG

#define PP_FLAG 0x2000

BUS state flags.

Definition at line 40 of file gpib.h.

◆ REN_FLAG

#define REN_FLAG 0x0800

Definition at line 36 of file gpib.h.

◆ SRQ_FLAG

#define SRQ_FLAG 0x0200

Definition at line 34 of file gpib.h.

◆ STATUS_MASK

#define STATUS_MASK 0xff00

Definition at line 54 of file gpib.h.

◆ TIMEOUT_FLAG

#define TIMEOUT_FLAG 0x4000

Definition at line 41 of file gpib.h.

◆ TRACE_ALL

#define TRACE_ALL 1 /* trace all bus states durring a read */

arguments to gpib_read_byte

Definition at line 65 of file gpib.h.

Enumeration Type Documentation

◆ anonymous enum

anonymous enum

GPIB read trace states.

Enumerator
TRACE_DISABLE
TRACE_READ
TRACE_BUS

Definition at line 57 of file gpib.h.

◆ anonymous enum

anonymous enum

Enumerator
GPIB_RX_START
GPIB_RX_WAIT_FOR_DAV_LOW
GPIB_RX_DAV_IS_LOW
GPIB_RX_WAIT_FOR_NDAC_HI
GPIB_RX_WAIT_FOR_DAV_HI
GPIB_RX_DAV_IS_HI
GPIB_RX_FINISH
GPIB_RX_ERROR
GPIB_RX_DONE

Definition at line 68 of file gpib.h.

◆ anonymous enum

anonymous enum

Enumerator
GPIB_TX_START
GPIB_TX_WAIT_FOR_NRFD_OR_NDAC_LOW
GPIB_TX_PUT_DATA
GPIB_TX_WAIT_FOR_NRFD_HI
GPIB_TX_SET_DAV_LOW
GPIB_TX_WAIT_FOR_NDAC_HI
GPIB_TX_SET_DAV_HI
GPIB_TX_FINISH
GPIB_TX_ERROR
GPIB_TX_DONE

Definition at line 81 of file gpib.h.

◆ anonymous enum

anonymous enum

Enumerator
GPIB_PP_IDLE
GPIB_PP_DETECTED

Definition at line 95 of file gpib.h.

Function Documentation

◆ gpib_bus_init()

void gpib_bus_init ( )

Initialize/Release GPIB Bus control lines Used for Power ON, Reset or IFC LOW reset conditions.

Returns: void

FIXME verify resetting gpib_unread_f is ALWAYS correct when called

Definition at line 229 of file gpib.c.

Referenced by gpib_init_devices(), gpib_read_byte(), gpib_write_byte(), and main().

◆ gpib_bus_read()

uint8_t gpib_bus_read ( )

Read GPIB data BUS only.

Returns: bus (lower 8 bits)

if a command byte (ATN low) then strip partity

Definition at line 562 of file gpib.c.

Referenced by gpib_read_byte().

◆ gpib_control_pin_read()

uint16_t gpib_control_pin_read ( )

Read GPIB control lines only FIXME V2 boards can only read pins enabled for read by the SN75162 FIXME We could add a test for read/write state ??

Returns: control lines (upper 8 bits)

See also: gpib_rx_init()

Definition at line 580 of file gpib.c.

Referenced by gpib_read_byte().

◆ gpib_decode()

void gpib_decode ( uint16_t ch )

Calls gpib_decode_str() and dosplays the result.

Display: decode/display all control flags and data on GPIB BUS.

See also: gpib_decode_str()

Returns: void

Definition at line 1266 of file gpib.c.

Referenced by gpib_read_str(), gpib_task(), gpib_trace_task(), and gpib_write_str().

◆ gpib_decode_header()

void gpib_decode_header ( FILE * fo )

Displays help for gpib_decode() function.

You would call this once at the start of a trace for example.

See also: : gpib.h _FLAGS defines for a full list is control lines we track; : gpib_trace()

Returns: void

Parameters

[in] fo FILE pointer or "stdout"

Definition at line 1082 of file gpib.c.

Referenced by gpib_trace_task().

◆ gpib_detect_PP()

uint8_t gpib_detect_PP ( )

Attempt to detect the Parallel Poll Reposnse state Used only for debugging - it is unlikely that we will catch this state V2 hardware - this does not work unless reading BUS.

PPR is short for "Parellel Poll Response"
PPR happens when the CIC (controller in charge) holds BOTH of ATN == 0 and EOI == 0
PPR Response happens using hardware The hardware pulls a bit low on the GPIB bus corresponding to the device. But only if any PPR mask bits are set in the hardware
Note: EOI is never used in command mode (ATN = 0) 1) Hardware will automatically hold GPIB DATA BUS lines low
ppr_reg() determines if we have PPR enabled.
References:
- SS80 pg 3-4, section 3-3
  See also
  gpib_enable_PPR()
  
  gpib_disable_PPR()
  
  Returns
  1 if we see a PPR, 0 if not

FIXME we can only read EOI in bus READ mode

Bus pin states but do not alter port direction state

debugging - read the ddr data direction bits to determine read/write state

FIXME we can only read EOI in bus READ mode FIXME We add a test for read/write state ??

Definition at line 469 of file gpib.c.

Referenced by gpib_read_byte(), and gpib_write_byte().

◆ gpib_disable_PPR()

void gpib_disable_PPR ( int bit )

Disable PPR (Parallel Poll Response) for a device.

Reference: SS80 pg 3-4, section 3-3
Returns
void

Definition at line 436 of file gpib.c.

Referenced by GPIB_SECONDARY_ADDRESS(), SS80_Command_State(), SS80_COMMANDS(), SS80_Execute_State(), SS80_init(), and SS80_Transparent_State().

◆ gpib_enable_PPR()

void gpib_enable_PPR ( int bit )

Reference: SS80 pg 3-4, section 3-3
Returns
void

Definition at line 416 of file gpib.c.

Referenced by SS80_Amigo_Clear(), SS80_Cancel(), SS80_Channel_Independent_Clear(), SS80_Command_State(), SS80_Execute_State(), SS80_Selected_Device_Clear(), SS80_Transparent_State(), and SS80_Universal_Device_Clear().

◆ gpib_handshake_pin_read()

uint16_t gpib_handshake_pin_read ( )

Read GPIB handshake lines only FIXME: V2 boards can only read pins enabled for read by the SN75162 FIXME We could add a test for read/write state ??

Returns: handshake lines (upper 8 bits)

for tracing we can reuse the error flag bit values for DAV,NRFD and NDAC FYI: This has no impact on the gpib_read_byte() functions and return values

Definition at line 601 of file gpib.c.

Referenced by gpib_read_byte().

◆ gpib_read_byte()

uint16_t gpib_read_byte ( int trace )

read 1 byte and control line status from GPIB BUS

Parameters

[in] trace if non-zero do full bus handshake trace of read

References: HP-IB Tutorial pg 13, 14.
Notes: Their diagram is a bit misleading - they start in the BUS init phase. The init happens much earlier in other code - we NEVER want to do that here or bad things will happen - we could step on the sender NRFD test and false trigger it. We instead start with NRFD FLOAT, and NDAC LOW. See loop in send diagram it has NDAC == 0 and NRFD == 1 in the return to send (beginning) part of the loop.
The HP-IB reference has an error: Read ready actually starts when NRFD = 1 and NDAC = 0. If you look at the Write state diagram that can be confirmed.

Returns

Lower 8 bits: Data or Command.
- If ATN is LOW then we strip parity from the byte.
Upper 8 bits: Status and Errors.

See also

gpib.h _FLAGS defines for a full list.

An error implies the data byte can't be trusted
Control Line Flags.
- EOI_FLAG
- SRQ_FLAG
- ATN_FLAG
- REN_FLAG
- PP_FLAG
Error Flags:
- IFC_FLAG

Returns: (data bus, control and error status)

V2 boards can NOT read ALL bits on the control bus at once

DAV must be high

V2 boards can NOT read all control bits at once NRFD,NDAC and SRQ are cirrently outputs

Wait for DAV HI

Ready for next byte

V2 boards can not read all control and handshake bits at once FIXME We could add a test for read/write state ?? NRFD,NDAC SRQ are outputs durring write phase, but not at very start

Note: see: HP-IB Tutorial pg 13

Remember that NDAC and NRFD are now both LOW!
The spec says to KEEP BOTH LOW when NOT ready to read otherwise we may miss a transfer and cause a controller timeout!
GPIB TX state expects NRFD LOW on entry or it is an ERROR!

Definition at line 875 of file gpib.c.

Referenced by gpib_read_str(), gpib_task(), and gpib_trace_task().

◆ gpib_read_str()

int gpib_read_str	(	uint8_t *	buf,
		int	size,
		uint16_t *	status
	)

Read string from GPIB BUS - controlled by status flags.

Status flags used when reading
- If EOI is set then EOI detection will end reading when EOI is detected.
- If an early or unexpected EOI is detected a warning is displayed.
- The state of ATN controls the type of data read.
  - If ATN is set then parity is stripped.
  - Only data matching the ATN flag state set by user is read.
    - If we see a mismatch we "unread" it and exit.
    - Unreading saves data AND status to be reread later on.

See also: : gpib_read_byte(); : gpib_unread()

Parameters

[in]	buf	Binary gpib string to read
[in]	size	Size of string we want to read
[in]	status	controls sending modes and returns status

Returns: bytes read; status

Errors TIMEOUT_FLAG or IFC_FLAG will cause early exit and set status.
- Lower 8 bits: Data or Command.
  - If ATN is LOW then we strip parity from the byte.
- Upper 8 bits: Status and Errors.
  - See also
    gpib.h _FLAGS defines for a full list.
  - An error implies the data byte can't be trusted
  - Control Line Flags.
    - EOI_FLAG
    - SRQ_FLAG
    - ATN_FLAG
    - REN_FLAG
    - PP_FLAG
  - Error Flags:
    - IFC_FLAG

Todo:: TODO decode this state - for now I just set the EOI_FLAG

Definition at line 1307 of file gpib.c.

Referenced by SS80_Amigo_Clear(), SS80_Command_State(), SS80_locate_and_write(), and SS80_Transparent_State().

◆ gpib_rx_init()

void gpib_rx_init ( uint8_t busy )

Initialize GPIB Bus control lines for READ.

Set busy = 0 after powerup everying floating or high
- If busy = 1 NRFD/NDAC are set to busy low
References:
- HP-IB Tutorial
- HP-IB pg 8-11
  Returns
  void

Definition at line 307 of file gpib.c.

Referenced by gpib_read_byte(), gpib_write_byte(), and gpib_write_str().

◆ gpib_state_init()

void gpib_state_init ( void )

Reset GPIB states and related variables.

Called at powerup and IFC or reset states.
Does not reset BUS
Returns
void

Definition at line 389 of file gpib.c.

Referenced by gpib_init_devices(), and main().

◆ gpib_timeout_set()

void gpib_timeout_set ( uint32_t time )

Set GPIB timeout timer in units of GPIB_TASK_TIC_US.

See also: : gpib_timeout_test()

Returns: void

Definition at line 207 of file gpib.c.

Referenced by gpib_read_byte(), gpib_write_byte(), and gpib_write_str().

◆ gpib_timeout_test()

uint8_t gpib_timeout_test ( )

Test GPIB timeout timer for timeout condition.

See also: : gpib_timeout_set()

Returns: 1 if timeout, 0 if not

Definition at line 220 of file gpib.c.

Referenced by gpib_read_byte(), gpib_write_byte(), and gpib_write_str().

◆ gpib_timer_elapsed_begin()

void gpib_timer_elapsed_begin ( void )

Start measuring time - used with hpib_timer_elapsed_end()

See gpib_hal.c for CPU specific code Provide Elapsed timer and Timeout timer - both in Microseconds We use the lower level clock elapsed timer functions here

Returns: void

Definition at line 133 of file gpib.c.

Referenced by gpib_detect_PP(), gpib_tests(), SS80_locate_and_read(), and SS80_locate_and_write().

◆ gpib_timer_elapsed_end()

void gpib_timer_elapsed_end ( char * msg )

Display user message and time delta since gpib_timer_elapsed_begin() call.

Display a message

Returns: void

Definition at line 164 of file gpib.c.

Referenced by gpib_detect_PP(), gpib_tests(), SS80_locate_and_read(), and SS80_locate_and_write().

◆ gpib_timer_reset()

void gpib_timer_reset ( void )

Reset elapsed and timeout timers Elapses and Timeout Timers.

Returns: void

Definition at line 150 of file gpib.c.

Referenced by gpib_timer_init().

◆ gpib_timer_task()

void gpib_timer_task ( )

Main GPIB timer task called by low level interrup hander.

Provides Down timers and Elapsed timers
Called every GPIB_TASK_TIC_US Micro Seconds
Returns
void

Definition at line 190 of file gpib.c.

Referenced by gpib_timer_init().

◆ gpib_trace_display()

void gpib_trace_display	(	uint16_t	status,
		int	trace_state
	)

decode/display all control flags and data on the GPIB BUS

Parameters

[in]	status	data bus value (lower 8 bits) control bus (upper 8 bits)
[in]	trace_state	level of trace detail TRACE_DISABLE = normal bus and control status report from read state only TRACE_READ = trace bus and control reporting from read state only TRACE_BUS = trace control reporting from all non-read states, data bus values are omiited Note: trace states add DAV,NRFD,NDAC and ommit PPR status, BUS error and timeout given that gpib_read_byte() report these anyway Lower 8 bits: Data or Command. If ATN is LOW then we strip parity from the byte. Upper 8 bits: Status and Errors.

See also

gpib.h _FLAGS defines for a full list.

An error implies the data byte can't be trusted
Control Line Flags.
- EOI_FLAG
- SRQ_FLAG
- ATN_FLAG
- REN_FLAG
- PP_FLAG
Error Flags:
- IFC_FLAG

Parameters

[in] str string pointer to store the decoded result in.

See also: : gpib_read_byte(); : gpib_write_byte(int ch); : gpib_decode_header()

Returns: void Note the bits we can read depends on what hardware verions we have V2 hardware can only read status bits based on GPIB control buffer direction FIXME We could add a test for read/write state ??

Definition at line 1135 of file gpib.c.

Referenced by gpib_decode(), and gpib_read_byte().

◆ gpib_tx_init()

void gpib_tx_init ( )

Initialize GPIB Bus control lines for WRITE.

Set busy = 0 after powerup everying floating or high
- If busy = 1 NRFD/NDAC are set to busy low
References:
- HP-IB Tutorial
- HP-IB pg 8-11
  Returns
  void

Definition at line 364 of file gpib.c.

Referenced by gpib_write_byte().

◆ gpib_unread()

uint16_t gpib_unread ( uint16_t ch )

GPIB ungets one character and all status states.

Pushes a character back into the read buffer

Parameters

[in]

ch

Lower 8 bits: Data or Command.
- If ATN is LOW then we strip parity from the byte.
Upper 8 bits: Status and Errors present.

See also: gpib.h _FLAGS defines for a full list.

Returns: ch

Definition at line 544 of file gpib.c.

Referenced by GPIB_COMMANDS(), and gpib_read_str().

◆ gpib_write_byte()

uint16_t gpib_write_byte ( uint16_t ch )

Send 1 byte and control line states to GPIB BUS.

NOTE We are ONLY called via gpib_write_str
We have been addressed by the active controller to talk We always arrive here in READ read state.
- Any error flags set on return imply the data was not likely sent
- You can OR the control flags ATN_FLAG, EOI_FLAG with (ch) to send them these states.
- Results can be displayed for debugging with the decode(ch) funnction
- We always exit with NRFD and NDAC LOW
References: HP-IB Tutorial pg13. HP-IB Tutorial pg 13 for the receive and send control line states Correction: The send routine MUST also wait for NDAC LOW before exit. (You can verify this by checking the receive part of the handshake diagram just before it returns to the start of the loop) Failing to wait will cause problems that may masqurade as timing issues.
(It caused problems with my HP85 before I added the code)

Parameters

[out]

ch

( Data or Command ) and control flags

Upper 8 bits: contril flags
Flags:
- EOI_FLAG
- ATN_FLAG
  - EOI and ATN can only be used in controller mode

Returns

Lower 8 bits: Data or Command.
- If ATN is LOW then we strip parity from the byte.
Upper 8 bits: Status and Errors.

See also

gpib.h _FLAGS defines for a full list.

An error implies the data byte can't be trusted
Control Line Flags.
- EOI_FLAG
- SRQ_FLAG
- ATN_FLAG
- REN_FLAG
- PP_FLAG
Error Flags:
- IFC_FLAG

ALL devices are ready

@release BUS

Definition at line 655 of file gpib.c.

Referenced by gpib_write_str().

◆ gpib_write_str()

int gpib_write_str	(	uint8_t *	buf,
		int	size,
		uint16_t *	status
	)

Send string to GPIB BUS - controlled by status flags.

Status flags used when sending
- If EOI is set then EOI is sent at last character

Parameters

[in]	buf	Binary gpib string to send
[in]	size	Size of string
[in]	status	User status flags that control the sending process.

Returns

bytes sent

will match size on success (no other tests needed).
Any size mismatch impiles error flags IFC_FLAG and TIMEOUT_FLAG.

Errors TIMEOUT_FLAG or IFC_FLAG will cause early exit and set status.
- Lower 8 bits: Data or Command.
  - If ATN is LOW then we strip parity from the byte.
- Upper 8 bits: Status and Errors.
  - See also
    gpib.h _FLAGS defines for a full list.
  - An error implies the data byte can't be trusted
  - Control Line Flags.
    - EOI_FLAG
    - SRQ_FLAG
    - ATN_FLAG
    - REN_FLAG
    - PP_FLAG
  - Error Flags:
    - IFC_FLAG
      See also
      : gpib_write_byte()
      
      : gpib.h _FLAGS defines for a full list)

Returns: Returns

Definition at line 1396 of file gpib.c.

Referenced by Send_Identify(), SS80_describe(), SS80_error_return(), SS80_locate_and_read(), SS80_Report(), and SS80_send_status().

Variable Documentation

◆ current

uint16_t current

Definition at line 97 of file gpib.c.

Referenced by clock_elapsed_end(), gpib_read_byte(), and gpib_state_init().

◆ debuglevel

int debuglevel

Debug flag - used to log GPIB and emulator messages.

Definition at line 33 of file gpib_task.c.

◆ device

uint8_t device

◆ gpib_iobuff

uint8_t gpib_iobuff[GPIB_IOBUFF_LEN]

common IO buffer for gpib_read_str() and gpib_write_str()

Definition at line 77 of file gpib.c.

Referenced by SS80_Command_State(), SS80_locate_and_read(), SS80_locate_and_write(), and SS80_Transparent_State().

◆ lastcmd

uint16_t lastcmd

Definition at line 112 of file gpib.h.

◆ listening

uint8_t listening

gpib listen address

Definition at line 90 of file gpib.c.

◆ listening_last

uint8_t listening_last

gpib last listen address

Definition at line 92 of file gpib.c.

Referenced by GPIB_LISTEN(), gpib_state_init(), and listen_cleanup().

◆ secondary

uint8_t secondary

gpib secondary

Definition at line 100 of file gpib.c.

Referenced by GPIB_COMMANDS(), gpib_state_init(), and gpib_task().

◆ spoll

uint8_t spoll

gpib serial poll status

Definition at line 95 of file gpib.c.

◆ talk31

uint8_t talk31

◆ talking

uint8_t talking

gpib talk address

Definition at line 85 of file gpib.c.

◆ talking_last

uint8_t talking_last

gpib last talk address

Definition at line 87 of file gpib.c.

Referenced by gpib_state_init(), and GPIB_TALK().

Macros

Enumerations

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ ATN_FLAG

◆ BUS_ERROR_FLAG

◆ CMD_MASK

◆ CONTROL_MASK

◆ DATA_MASK

◆ DAV_FLAG

◆ EOI_FLAG

◆ ERROR_MASK

◆ GPIB_BUS_SETTLE_DELAY

◆ GPIB_IOBUFF_LEN

◆ HTIMEOUT

◆ IFC_FLAG

◆ NDAC_FLAG

◆ NO_TRACE

◆ NRFD_FLAG

◆ PP_FLAG

◆ REN_FLAG

◆ SRQ_FLAG

◆ STATUS_MASK

◆ TIMEOUT_FLAG

◆ TRACE_ALL

Enumeration Type Documentation

◆ anonymous enum

◆ anonymous enum

◆ anonymous enum

◆ anonymous enum

Function Documentation

◆ gpib_bus_init()

◆ gpib_bus_read()

◆ gpib_control_pin_read()

◆ gpib_decode()

◆ gpib_decode_header()

◆ gpib_detect_PP()

◆ gpib_disable_PPR()

◆ gpib_enable_PPR()

◆ gpib_handshake_pin_read()

◆ gpib_read_byte()

◆ gpib_read_str()

◆ gpib_rx_init()

◆ gpib_state_init()

◆ gpib_timeout_set()

◆ gpib_timeout_test()

◆ gpib_timer_elapsed_begin()

◆ gpib_timer_elapsed_end()

◆ gpib_timer_reset()

◆ gpib_timer_task()

◆ gpib_trace_display()

◆ gpib_tx_init()

◆ gpib_unread()

◆ gpib_write_byte()

◆ gpib_write_str()

Variable Documentation

◆ current

◆ debuglevel

◆ device

◆ gpib_iobuff

◆ lastcmd

◆ listening

◆ listening_last

◆ secondary

◆ spoll

◆ talk31

◆ talking

◆ talking_last