24c02 I2C TEST READ ERROR BUT WRITE WORKING GOOD IN RPI-HAL V5.1

[90999]

test code
`
program project1;
uses rpi_hal,pfio,sysutils;
var s:string;

begin

RPI_HW_Start([InitHaltOnError,InitGPIO,InitSPI,InitI2C]);
writeln('a');
I2C_string_write(RPI_I2C_busgen,$50,$20,#$01+#$02+#$34+#$56,NO_ERRHNDL);
writeln('b');
I2C_string_read(RPI_I2C_busgen,$50,$20,2,NO_ERRHNDL,s);
writeln(s);

end.
`

pi@raspberrypi:~/btest $ sudo ./project1
2019-10-03 10:24:57 WRN SPI_Dev_Init[0x00/00]: /dev/spidev0.0
2019-10-03 10:24:57 WRN SPI_Dev_Init[0x00/01]: /dev/spidev0.1
a
b
2019-10-03 10:24:57 ERR I2C_bus_WrRd[0x01/0x50]: failed to read device: (121) Remote I/O error

read 24c02 is error , but write 0x01023456 is OK 。

pi@raspberrypi:~/btest $ i2cdump -y 1 0x50
No size specified (using byte-data access)
0 1 2 3 4 5 6 7 8 9 a b c d e f 0123456789abcdef
00: 01 02 00 00 81 24 03 00 00 01 68 ff ff ff ff ff ??..?$?..?h.....
10: ff 0b 0c 0e ff ff ff ff ff ff ff ff ff ff ff ff .???............
20: 01 02 34 56 ff ff ff ff ff ff ff ff ff ff ff ff ??4V............

[90999]

something more

1）
when it need to write more then 8 byte data , it will cover the front address reg ,
d8(d0) d1 d2 d3 d4 d5 d6 d7 FF FF FF ...........

i think when length( xxxx ) + start address not 8*n , it must be cut .

0 7 8 11 15
66 77 88 99 d0 d1 d2 d3 /cut/ d4 d5 d6 d7 d8 FF FF FF

BUT .............

2）
I2C_string_write(...........
// I2C_string_read(............
I2C_string_write(............. //failed to read device: (121) Remote I/O error
I2C_string_read(..................
@^#&^@!&#@! // it 's working ~~~~~~~~~ :D

something likes chip not end in busy (ACK/NACK) or wait it timeout ?

I2C_string_write(........... //working!
sleep(1);
I2C_string_read(............ //working!
sleep(1);
I2C_string_write(............. //working!
sleep(1);
I2C_string_read(.................. //working!

so................. it's all my problem ?

[rudiratlos]

you can set in /boot/config.txt

dtparam=i2c_baudrate=400000